Integrated Circuit Package Holder

1. Field of the Invention

The present invention relates to an integrated circuit package holder comprising conductive pins subjacent to the holder into which conductive pins of the package are plugged.

More particularly, this invention deals with safeguarding binary information in an integrated circuit, such as a memory, when power delivered by a main power source of a printed circuit board on which the holder is mounted, disappears for any reason. Provisions must be made for a spare power source that can replace the main power source in order to save the information stored in the memory, or at least an essential logic function performed by the integrated circuit, such as a clock signal generation.

2. Description of the Prior Art

Two solutions for mounting a spare power source that can feed integrated circuits have already been proposed. The spare source generally consists of several cells or miniature accumulators.

In a first solution, the spare power source is housed in a cylindrical or parallelepipedal flat package mounted directly on the printed circuit board. The spare power source package takes up some noticeable space on the printed circuit board thereby cutting the number of integrated circuits that could have been mounted on the board. Further, additional printed electrical conductors are required to connect the spare power source to integrated circuit supply terminals.

A second solution consists of housing the spare power source inside the integrated circuit package. The cost of the integrated circuit is then high. If the integrated circuit or the spare power source becomes defective, the whole package must be changed, as the spare source is not accessible alone.

In an embodiment of the second solution disclosed in international patent application No. WO 82/04359, the spare power source is removably inserted in an open recess located in one major overlying side of the integrated circuit package opposite the printed circuit board. Such package must be designed for each specific integrated circuit and replacement of the integrated circuit requires replacement of the whole package.

The main object of the invention is to obviate the drawbacks of mounting spare power sources as per the prior art.

Another object of the invention is to replace easily and inexpensively a spare power source located beneath a standard integrated-circuit package, without substantially increasing the space already provided for the integrated circuit package on a printed circuit board.

Another object of the invention is to fixedly connect conductive pins of an electronic circuit package to conductive pins of a package holder without any soldering.

Another object of the invention is to plug conductive pins of an electronic circuit package into conductive pins of a package holder and to lock the package and the holder by means of single pressures exerted onto the pakage.

Another object of the invention is to withdraw an electronic circuit package from a package holder containing a removable spare power source without withdrawing the spare source from the holder.

Another object of the invention is to monitor a voltage between terminals of a spare power source included in an electronic circuit package holder.

Another object of the invention is to display a discharge of a spare power source included in an electronic circuit package holder.

A further object of the invention is to inhibit a predetermined function of an integrated circuit package mounted on a package holder when a discharge voltage threshold of a spare power source contained in the hold is reached.

In accordance with the aforementioned objects, an integrated circuit package holder comprises conductive pins in which conductive pins of the package are respectively plugged, a recess preferably located between two conductive holder pin rows for receiving a removable spare power source to be interconnected between two predetermined holder pins in which supply pins of the package are plugged. The conductive holder pins have tails underlying to the holder and soldered to conductive strips of a printed circuit board and have contacts overlying to the holder and receiving the package pins.

Use is thus made in the invention of the space available between an integrated circuit package and the printed circuit board to insert a holder embodying the invention, having dimensions analogous with the package dimensions but including a spare power source. The height of an arrangement including the superposed package and holder is substantially small by the use of cells or miniature accumulators of the button type, as a spare power source, already used elsewhere for microcomputers, watches or electronic games. The cost of adding the spare source is whittled down even more in that the spare source relies on cells or accumulators that are widely available on the market. In addition, the spare source is removable from the holder thereby eschewing complete replacement of the holder or integrated circuit package whenever the spare source is defective.

According to other features of this invention, a cover removable from the holder is inserted between the circuit package and the holder. The cover is molded in a resilient plastic. The cover is provided with locking means for locking the cover and the holder to hold the removable spare source in the holder, and for locking the package and the holder in order to fixedly connect the package pins to the holder pins without any soldering.

An unlocking operation between the package and the holder can be accomplished without unlocking the cover from the holder in order to withdraw the package and hold the spare source in the holder. Locking and unlocking operations are simply carried out by pressures exerted onto the cover and the holder.

According to a further feature of the invention, the holder carries monitoring means for detecting a voltage across terminals of the spare power source lower than a predetermined source discharge threshold. The monitoring means visually and/or acoustically indicates a start of the discharge from the spare source with a view to replacing the spare source and to saving a function or a stored information of the integrated circuit.

According to a further feature of the invention, the holder carries means for inhibiting a predetermined function of the integrated circuit whenever the main supply source voltage of the printed circuit board across the supply pins disappears. When the integrated circuit is a memory, the function to be inhibited can be a writing authorization in the memory.

The foregoing and other objects, features and advantages of the invention will be apparent from the following detailed description of several preferred embodiments of the invention with reference to the corresponding accompanying drawings in which:

FIG. 1 is an exploded view in perspective of an integrated circuit package holder embodying the invention, comprising two head-to-tail and juxtaposed spare button cells having axes perpendicular to major sides of the package;

FIG. 2 is a schematic side view of the holder shown in FIG. 1, mounted on a printed circuit board;

FIG. 3 is a schematic plan view of two holders as shown in FIG. 1, fed by a main power source of the printed circuit board;

FIG. 4 is a schematic plan view of three holders embodying the invention, one of which is a spare for the other two;

FIG. 5 is a detailed view in perspective of a holder upright in FIG. 4, showing one of supply conductive strips of the holder;

FIG. 6 is a schematic cross-sectional view of a holder embodying the invention, having a molded cavity to receive a spare power source;

FIG. 7 is a partial view in perspective of a holder embodying the invention, having a cavity sealed by a cover and receiving two juxtaposed button cells;

FIG. 8 is a schematic view in perspective of another holder having a cavity to receive two head-to-tail and juxtaposed button cells having axes parallel to major sides of the integrated circuit package;

FIG. 9 is a schematic view in perspective of the holder shown in FIG. 8, fitted with a cover shutting off the cavity;

FIG. 10 is an exploded view in perspective of another integrated circuit package holder embodying the invention, housing three juxtaposed spare button-cells, the holder being assembled with a removable cover intended for connecting and disconnecting integrated circuit pins and the holder pins with no soldering, simply by pressing on the package;

FIGS. 11A to 11H schematically show various cell arrangements in holders having two or three cell recesses and a spare power source switch shown in FIG. 10, respectively;

FIG. 12 is a detailed side view partially cross-sectional showing the holder and cover in FIG. 10, and depicting a supply pin of the holder after the cover and holder have been clipped shut by first locking means and before the integrated circuit package of the holder is locked;

FIG. 13 is a view in perspective of second cover and holder locking means for the embodiment in FIG. 10;

FIGS. 14A to 14E are cross-sectional views of the second locking means at various stages of the cover and the package being shut and of the package being opened with respect to the holder, respectively;

FIG. 15 is a schematic view in perspective of an electrical connection between a contact reed relative to a cell and a positive supply pin of the holder as in FIG. 10;

FIG. 16 is a schematic exploded view in perspective of an electrical connection between another contact reed relative to another cell and a negative supply pin of the holder as in FIG. 10;

FIG. 17 is a view in perspective of a specific sleeve of a supply pin of the holder as in FIG. 10;

FIG. 18 is an exploded view in perspective of another integrated circuit package holder embodying the invention, having two spare button cells superposed parallel to major sides of an integrated circuit package, as well as a package containing a spare cell voltage monitoring circuit and/or a function inhibiting circuit;

FIG. 19 is a block diagram of the monitoring circuit;

FIGS. 20, 21, 22 are schematic views in cross-section, from above and longitudinally of a package containing the monitoring circuit, respectively;

FIG. 23 is a block diagram of a monitoring circuit common to six holders embodying the invention;

FIG. 24 depicts another embodiment of connection of a display device in the monitoring circuit in FIG. 23; and

FIG. 25 is a block diagram of the function inhibiting circuit.

In a first embodiment mode depicted in FIG. 1, a holder 1 is intended to carry a standard integrated circuit package 2 having 28 metallic pins 20.sub.1 to 20.sub.28. Package 2 is parallelepipedal and flat in shape and is a dual-in-line package, i.e. the pins are arranged in two rows 20.sub.1 to 20.sub.14 and 20.sub.15 to 20.sub.28 extending vertically under longitudinal sides of package 2. Two adjacent pins in either of the two rows are separated by a standard pitch p=2.54 mm for integrated circuits. At least an integrated circuit chip is encapsulated in package 2 and can be a CMOS-technology memory such as a random access memory RAM.

Holder 1 is made of moulded plastic and is also parallelepipedal in shape with dimensions substantially greater than those of package 2. Holder 1 also comprises two longitudinal rows of vertical metallic pins 10.sub.1 to 10.sub.14 and 10.sub.15 to 10.sub.28 protruding beneath the holder. Each pin 10.sub.1 to 10.sub.28 of the holder is terminated upwardly by a sleeve 11.sub.1 to 11.sub.28 having, for example, small vertically extending resilient conductive strips. Sleeve 11.sub.1 to 11.sub.28 is integral with holder 1 in a vertically extending suitable hole in holder 1 in order to receive a respective vertical pin 20.sub.1 to 20.sub.28 of package 2 duly plugged therein. Electrically conductive pins 10.sub.1 to 10.sub.28 are respectively connected by wrapping or soldering to electrically conductive strips, such as a strip 30, on a printed circuit board 3 shown in FIG. 2 or 3. In the latter case, lower bases of sleeves 11.sub.1 to 11.sub.28 butt against the surface of the printed circuit board above metal-plated holes in the board through which pins 10.sub.1 to 10.sub.28 run. As schematically shown in FIG. 2, holder 1 is located between package 2 and board 3, and each pin 10.sub.1 to 10.sub.28 electrically links a respective pin 20.sub.1 to 20.sub.28 to at least one conductive strip printed on board 3, such as conductive strip 30.

Holder 1 has a U-shaped cross-section with upwardly and vertically extending arms and oriented towards package 2. The longitudinal arms of the U-shaped cross-section form side-members 12.sub.1 and 12.sub.2 carrying vertical holes to respectively contain sleeves 11.sub.1 to 11.sub.14 and 11.sub.15 to 11.sub.28. A central cross-member 13.sub.0 and two end cross-members 13.sub.1 and 13.sub.2 of holder 1 tie side-members 12.sub.1 and 12.sub.2 and together form two square slots 14.sub.1 and 14.sub.2.

Slots 14.sub.1 and 14.sub.2 constitute recesses to respectively receive two miniature cells of the button type, 4.sub.1 and 4.sub.2, constituting a spare power source. The cells can be known types based on silver, mercury or preferably lithium, frequently used in microelectronics. Disk-shaped metallic surfaces on the surfaces of each cell 4.sub.1 and 4.sub.2 make up a positive terminal 40.sub.1.sup.+, 40.sub.2.sup.+ and a negative terminal 40.sub.1.sup.-, 40.sub.2.sup.- of the cell. As illustrated in FIG. 1, the metallic surface forming the cell positive terminal fully covers one side of the cell and an external cylindrical contour of the cell, whereas the metallic surface forming the cell negative terminal is a projecting surface that is concentric with the other side of the cell and is smaller in diameter than said cell side.

Each cell can be replaced by a miniature battery of accumulators, in lead or cadmium/nickel for instance. The accumulator battery is then rechargeable from a main power source MPS to the printed circuit.

Generally, each elementary spared power source such as a cell 4.sub.1, 4.sub.2 is a small sealed housing and delivers a voltage equal at the most to 1.5 volt. Two series-connected cells produce a voltage of some 2 to 3 volts that can take over from a main power source in the event of failure in an integrated circuit.

Cells 4.sub.1 and 4.sub.2 are removably inserted in slots 14.sub.1 and 14.sub.2 in holder 1 and are wired up in series as shown in FIG. 3.

Positive terminal 40.sub.1.sup.+ of first cell 4.sub.1 is connected to an anode of a clamping diode D.sub.1 via a substantially horizontally extending contact reed 15.sub.+ and a sleeve 11.sub.T of a test pin 10.sub.T of holder 1. Reed 15.sub.+ is pan-shaped and made of a semi-rigid or resilient electrically conductive material. A circular portion of reed 15.sub.+ is subject to the middle of slot 14.sub.1 and bears disk-shaped terminal 40.sub.1.sup.+. A tail of reed 15.sub.+ extends substantially longitudinally in holder 1 and is soldered to the lower base of sleeve 11.sub.T of test pin 10.sub.T situated beneath cross-member 13.sub.1 between pins 10.sub.1 and 10.sub.28. The diode D.sub.1 is preferably fully embedded in cross-member 13.sub.1 although, in another embodiments, the diode D.sub.1 can be laid on cross-member 13.sub.1. The anode of diode D.sub.1 is soldered to sleeve 11.sub.T. A cathode of diode D.sub.1 is soldered to sleeve 11.sub.1 of pin 10.sub.1. Sleeve 11.sub.1 receives package pin 20.sub.1 which forms a positive supply terminal for the integrated circuit. As shown in FIG. 3, pin 10.sub.1 is soldered to a conductive strip 30.sub.+ printed on board 3. The strip 30.sub.+ is connected to a positive terminal MPS.sub.+ of the printed circuit main power source MPS via a clamping diode D.sub.2 on board 3. An anode of diode D.sub.2 is connected to the positive main supply terminal MPS.sub.+, and a cathode of diode D.sub.2 is connected to negative terminal 40.sub.1.sup.+ of cell 4.sub.1 through printed strip 30.sub.+ and diode D.sub.1.

A negative supply terminal of the integrated circuit in package 2 is made up of pin 20.sub.15 diagonally opposite positive supply pin 20.sub.1. Pin 20.sub.15 is connected to negative terminal 40.sub.2.sup.- of second cell 4.sub.2 also via a pan-shaped contact reed 15.sub.- made of a resilient electrically conductive material. A circular portion of reed 15.sub.- is subjacent to the middle of second slot 14.sub.2 and receives negative dish-shaped terminal 40.sub.2.sup.- of cell 4.sub.2. A tail of reed 15.sub.- is bent and soldered to the lower base of sleeve 11.sub.15 of pin 10.sub.15 beneath side-member 12.sub.2. As depicted in FIG. 3, pin 10.sub.15 is soldered to a conductive strip 30.sub.- printed on board 3 connected directly to a ground referred terminal MPS.sub.- of the main supply MPS. The main power source MPS and spare power source 4.sub.1 -4.sub.2 are connected in parallel between terminals 20.sub.1 and 20.sub.15 by means of clamping diodes D.sub.1 and D.sub.2, whereby it is possible to hold a virtually constant supply voltage in the event of failure in the main power source.

As shown in FIG. 1, negative terminal 40.sub.1.sup.- of first cell 4.sub.1 is connected to positive terminal 40.sub.2.sup.+ of second cell 4.sub.2 via a connecting plate 5 made of a resilient electrically conductive material. Plate 5 is rectangular and extends longitudinally on either side of central cross-member 13.sub.0. Two downwardly extending transverse tabs 51 from the middle of plate 5 plug into two vertical holes 131 in central cross-member 13.sub.0 and, simultaneously, contact tips 52.sub.1 and 52.sub.2 of plate 5 come into pressure contact with cell terminals 40.sub.1.sup.- and 40.sub.2.sup.+. In holder 1, each cell 4.sub.1, 4.sub.2 is thus held between respective reed 15.sub.+, 15.sub.- and respective tips 52.sub.1, 52.sub.2 of plate 5. Reeds 15.sub.+ and 15.sub.- can be substantially bent upwards, and half-portions of plate 5 on either side of tabs 51 can be substantially bent downwards to pinch the cells more tightly. As shown in FIG. 2, cells 4.sub. 1 and 4.sub.2 are substantially thicker than holder 1, whereby a major surface underlying the package 2 is in pressure contact with plate 5, so that package 2 and holder 1 with the cells form an integral block. When necessary, the holder and package 2 assembly can be reinforced by soldering pins 20.sub.1 to 20.sub.28 to sleeves 11.sub.1 to 11.sub.28 respectively.

The capacitance of spare power source 4.sub.1 -4.sub.2 can be measured across test pin 10.sub.T and supply pin 10.sub.15.

Cell replacement is simply carried out by withdrawing package 2 from holder 1, i.e. by withdrawing pins 20.sub.1 to 20.sub.22 from sleeves 11.sub.1 to 11.sub.28 and then by lifting plate 5 such that tabs 51 are disengaged from holes 131. Package 2 is withdrawn using a known multi-pin extractor pliers.

In another embodiment, the connecting plate 5 runs across the central cross-member 13.sub.0 and is secured thereto and has contact ends 52.sub.1 and 52.sub.2 receiving in pressure contact the cell terminals 40.sub.1.sup.+ and 40.sub.1.sup.-. The contact reeds are replaced by two small contact reeds removable from holder 1 and analogous with a small connecting plate 52.sub.1 shown in FIG. 18. The small contact reeds are plugging into metallized holes in the end cross-member 13.sub.1 and 13.sub.2 respectively and are applied against the cell terminals 40.sub.1.sup.- and 40.sub.2.sup.+ in the slots 141.sub.1.sup.+ and 14.sub.1.sup.-. The metallized holes are respectively connected to the supply pins 10.sub.1 and 10.sub.15 through conductors embedded in holder cross-member 13.sub.1 and 13.sub.2. The small contact reeds can be sticked beneath the package 2.

FIG. 1 also shows a rectangular sheet of electrically insulating material 54. Sheet 54 extends horizontally between holder 1 and printed circuit board 3, and carries holes through which pins 10.sub.1 to 10.sub.28 of the holder fit. Once pins 10.sub.1 to 10.sub.28 have been soldered to board 3, and the holder 1 and package 2 have been assembled as depicted in FIG. 2, contact reeds 15.sub.+ and 15.sub.- can be substantially pushed towards board 3. Sheet 54 then electrically insulates reed 15.sub.+ in contact with positive terminal 40.sub.1.sup.+ of cell 4.sub.1 and reed 15.sub.- in contact with negative terminal 40.sub.2.sup.- of cell 4.sub.2 from the printed board strips located beneath holder 1.

Holder 1 further comprises two metallized supply strips 16.sub.+ and 16.sub.- that are secured to the external vertical and longitudinal edges on side-members 12.sub.1 and 12.sub.2 respectively, and two right-angle metallic spades 17.sub.+ and 17.sub.- having outwardly extending horizontal flats through which vertical supply pins 10.sub.1 and 10.sub.15 run and with which the pins 10.sub.1 and 10.sub.15 are soldered respectively. Strips 16.sub.+ and 16.sub.- and spades 17.sub.+ and 17.sub.- are provided such that several integrated-circuit holders embodying the invention that do not embody a spare power source can be fed from a spare power source in another holder embodying the invention.

In the example shown in FIG. 4, three integrated circuit holders 1A, 1B and 1C analogous with holder 1 embodying the invention are mounted between parallel printed strips 30.sub.+ and 30.sub.- on a printed circuit board 3. Strips 30.sub.+ and 30.sub.- are directly connected to the positive terminal MPS.sub.+ and the negative terminal MPS.sub.- on the main power source MPS normally feeding integrated circuits on the holders. In relation to each holder 1A, 1B, 1C, positive supply pin 10.sub.1 of the holder is soldered to one end of a short printed conductive strip 31.sub.+ having another end lying opposite strips 30.sub.+, and negative supply pin 10.sub.15 of the holder is soldered to one end of a second short printed conductive strip 31.sub.- having another end lying opposite conductor 30.sub.-.

It is assumed here that only the first holder 1A contains a spare power source having two cells 4.sub.1 and 4.sub.2. The main power source MPS feeds the integrated circuit on the holder 1A normally via a clamping diode D.sub.2 interconnected to strip 30.sub.+ and to the second end of respective short strip 31.sub.+, and via a strap st.sub.- extending between strip 30.sub.- and the second end of short strip 31.sub.-.

Electrical connections must be made for an integrated circuit carried by a holder having no spare power source, such as the holder 1B, to be supplied by spare source 4.sub.1 -4.sub.2 in the holder 1A should a failure occur, or normally from the main power source MPS. For each of holders 1A and 1B, upwardly extending flats of right-angle spades 17.sub.+ and 17.sub.- are respectively soldered to conductive strips 16.sub.+ and 16.sub.-. Ends of a first strap ST.sub.+ are soldered to the near-by ends of strips 16.sub.+ on the holders 1A and 1B respectively, and the ends of a second strap ST.sub.- are soldered to the near-by ends of strips 16.sub.- on the holders 1A and 1B respectively. Consequently, the positive supply terminal of the integrated circuit carried by the holder 1B is connected to the main power source positive terminal MPS.sub.+ across conductive members 11.sub.1, 10.sub.1, 17.sub.+ and 16.sub.- of the holder 1B, the strap ST.sub.+ , conductive members 16.sub.+, 17.sub.+ and 10.sub.1 of the holder 1A, short strip 31.sub.+ and diode D.sub.2 related to the holder 1A and printed strip 30.sub.+, and is connected to positive terminal 40.sub.1 + of spare power source 4.sub.1 -4.sub.2 in the holder 1A across conductive members 11.sub.1, 10.sub.1, 17.sub.+ and 16.sub.+ in holder 1B, the strap ST.sub.+ and conductive members 16.sub.+, 17.sub.+, 10.sub.1, 11.sub.1, D.sub.1, 11.sub.T and 15.sub.+ in the holder 1A. The negative supply terminal of the integrated circuit carried by holder 1B is connected to the main power source negative terminal MPS.sub.- across conductive members 11.sub.15, 10.sub.15, 17.sub.- and 16.sub.- of the holder 1B, the strap ST.sub.-, conductive members 16.sub.-, 17.sub.- and 10.sub.15 of the holder 1A, short strip 31.sub.- and the strap st.sub.- related to the holder 1A, and strip 30.sub.- and is connected to negative terminal 40.sub.2.sup.- of spare power source 4.sub.1 -4.sub.2 in the holder 1A across conductive members 11.sub.15, 10.sub.15, 17.sub.- and 16.sub.- of the holder 1B, the strap ST.sub.- and conductive members 16.sub.-, 17.sub.-, 10.sub.15 and 15.sub.- of the holder 1A. The connections around pin 10.sub.15 of the holder 1A are shown in detail in FIG. 5.

If an integrated circuit is carried by a holder having no spare power source, such as the holder 1C, and is directly fed from the main power source MPS by the inclusion of a short strap st.sub.+ between printed strip 30.sub.+ and short printed strip 31.sub.+ related to the holder 1C and by the inclusion of a second short strap st.sub.- between printed strip 30.sub.- and small printed strip 31.sub.- related to the holder 1C, one of two following solutions is possible to feed the integrated circuit from a spare source. A first solution consists of replacing the strap st.sub.+ related to the holder 1C by a clamping diode, such as diode D.sub.2, and of inserting two miniature spare cells into the holder 1C. A second solution consists of removing the straps st.sub.+ and st.sub.- related to the holder 1C and of introducing two straps, such as straps ST.sub.+ and ST.sub.-, between strips 16.sub.+ and 16.sub.- of the holder 1C and between strips 16.sub.+ and 16.sub.- of a neighbouring holder, such as the holder 1B, that is supplied by a spare source, respectively.

Conductive strips 16.sub.+ and 16.sub.- and conductive spades 17.sub.+ and 17.sub.- of the holder embodying the invention serve also for manually testing each of the cells contained in the holder.

Further embodiments of the integrated circuit package holder structure can also be envisioned for containing a suitable number of cells or miniature accumulator batteries depending on the supply voltage of the integrated circuit. A holder can carry four button cells when each cell 4.sub.1, 4.sub.2 is replaced by two slim-line cells superposed and connected in series, as will be seen in reference to FIGS. 11C and 11D. A holder can also offer three recesses that each receive a thick button cell or a pair of slim-line button cells, as will be seen in reference to FIGS. 11E to 11H. A holder can further offer two recesses each containing three very slim bottom cells stacked and connected in series. An increase in the number of cells is achieved by selecting cells of varying thickness. In all events, dimensions of the holder are matched with dimensions of the integrated-circuit package, and in particular the package pin number that can, for instance, be 14, 16, 20, 28 or 40, or 64 for a microprocessor.

Slots 14.sub.1 and 14.sub.2 can be closed off downwardly by molding in a bottom 140 to form two cavities, as shown schematically in FIG. 6; bottom 140 replaces insulating sheet 54 shown in FIGS. 1 and 2. Preferably, the horizontal cross-section of the recesses, such as slots 14.sub.1 and 14.sub.2, or cavities corresponds to the horizontal cross-section of the cells or accumulators in order to prevent any possible cell or accumulator movement in the holder. Plate 5 coupling cells 4.sub.1 and 4.sub.2, as depicted in FIG. 1, can be replaced by an adhesive copper film that is bonded beneath package 2; the copper film has ends coming into contact with terminals 40.sub.1.sup.- and 40.sub.2.sup.+ when pins 20.sub.1 to 20.sub.28 are plugged into sleeves 11.sub.1 to 11.sub.28.

A description is now given in detail of two embodiments of two-cell holders to enclose the cells hermetically, and one holder embodiment carrying at least three cells where the holder and the integrated circuit package can be easily and solidly assembled without any soldering.

In the embodiment illustrated in FIG. 7, two button cells, such as cell 4.sub.2, are respectively lodged in two molded circular cavities, such as cavity 14a.sub.2, lying parallel to major side of a 28-pin holder 1a. A discoid conductor 52a.sub.2 is printed on the bottom of cavity 14a.sub.2 or takes the form of a downwardly resilient circular metallic plate on the bottom of cavity 14a.sub.2. Conductor 52a.sub.2 is connected to an analogous conductor lodged on a bottom side of another molded cavity (not shown) through a conductor 5a embedded in holder 1a. Cavity 14a has a diameter substantially equal to the diameter of button cell 4.sub.2 and a depth substantially equal to the sum of the thicknesses of cell 4.sub.2 and a discoid cover 6.sub.2 both having a same outside diameter. To shut cavity 14a.sub.2 containing the cell 4.sub.2, cover 6.sub.2 is locked in place by a bayonet arrangement. Two locking lugs 61 and 62 are diametrically opposed and extend from the circumference of the cover facing cavity 14a.sub.2. An inner surface of cover 6.sub.2 facing terminal 40.sub.2.sup.- of cell 4.sub.2 carries a discoid printed conductor or a resilient circular metallic plate 63 fixed to the cover. Conductor 63 is extended by a tab 64 lying subjacent to lug 62. Provided at the circumference of cavity 14a.sub.2 are two diametrically opposed slits 141 and 142 and two blind circular grooves 143 and 144 also diametrically opposed and each running for a quarter of a turn. An end of each groove 143, 144 is formed by a respective slit 141, 142 designed to receive respective lug 61, 62 and another end of each groove forms a stop 145, 146 for respective lug 61, 62 after cover 6.sub.2 has been rotated through ninety degrees. Before stop 146, an end of a conductor 15a.sub.- emerges in the bottom of groove 144. Conductor 15a.sub.- is fully embedded in holder 1a and has another end connected to sleeve 11.sub.15 of negative supply pin 10.sub.15 . Once cover 6.sub.2 has been completely shut on cavity 14a.sub.2, tab 64 on cover 6.sub.2 engages conductor 15a.sub.-, thereby linking supply terminal 10.sub.15 to negative terminal 10.sub.2.sup.- of cell 4.sub.2. As far as cell 4.sub.1 is concerned, not shown in FIG. 7, a conductor analogous with conductor 15a connects terminal 40.sub.1.sup.+ of cell 4.sub.1 to sleeve 11.sub.T of test pin 10.sub.T via electrically conductive tab and disk secured on the underside of a respective cover analogous with cover 6.sub.2.

Conductive disks 52a.sub.2 and 63 are preferably resilient conductive plates with opposing deflections in order to ease withdrawal of the cover followed by extraction of the cell.

A surface of the holder 1a in which the cavities are included, such as cavity 14a.sub.2, housing cells 4.sub.1 and 4.sub.2 can be the holder 1a upper surface facing integrated circuit package 2 or the holder 1a lower surface facing printed circuit board 3, in which case pins 10.sub.1 to 10.sub.28 of the holder are sufficiently long to easily access to covers, such as cover 6.sub.2, as shown in FIG. 7.

Another holder substantially modified with respect to holder 1a in the aforegoing description in reference to FIG. 7 is now described. This other holder comprises just one cover, such as cover 6.sub.2, shutting off corresponding cavity 14a.sub.2 that communicates with the first cavity receiving cell 4.sub.1 through a passage-way having a width at least equal to the diameter of cells 4.sub.1 and 4.sub.2. The first cavity has parallel bottom wall and underwall formed by the full major sides of holder 1a. The two cavities thus form a continuous oblong cavity, accessible only via the opening to cavity 14a.sub.2. In this case, cell 4.sub.1 is inserted firstly into second cavity 14a.sub.2 and then pushed right into the other cavity along the passage-way. Second cell 4.sub.2 is inserted in cavity 14a.sub.2 that then is closed off by cover 6.sub.2. A small longitudinal hole between the first cavity and one transverse edge of holder 1a lateral thereto makes it possible to insert a rod for the purpose of working cell 4.sub.1 along towards cavity 14a.sub.2 so that cell 4.sub.1 may be withdrawn from holder 1a.

In a further embodiment depicted schematically in FIGS. 8 and 9, button cells 4.sub.1 and 4.sub.2 are vertically arranged and juxtaposed in a single parallelepipedal cavity 14b in a holder 1b. The axes of the cells run parallel to the major surfaces of package 2 and to printed circuit board 3. Holder 1b carries 14 pins 10.sub.1 to 10.sub.14 with sleeves 11.sub.1 to 11.sub.14 to receive 14 pins 20.sub.1 to 20.sub.14 of an integrated circuit package (not shown). Vertical longitudinal major sidewalls of holder 1b respectively bear two rows of pins 10.sub.1 to 10.sub.7 and 10.sub.8 to 10.sub.14. The sleeves of diagonally opposed pins 10.sub.1 to 10.sub.8 respectively receive positive and negative supply pins 20.sub.1 and 20.sub.8 of the integrated circuit package.

Cavity 14b has a width substantially equal to the thickness of cells 4.sub.1 and 4.sub.2. The cells are also arranged head-to-tail. Negative terminal 40.sub.1.sup.- of cell 4.sub.1 and positive terminal 40.sub.2.sup.+ of cell 4.sub.2 are in pressure contact with ends of a conductor 5b printed on or added to a vertical, longitudinal inner major surface of cavity 14b, whereas positive terminal 40.sub.1.sup.+ of cell 4.sub.1 and negative terminal 40.sub.2.sup.- of cell 4.sub.2 are in pressure contact with two respective resilient conductors 15b.sub.+ and 15b.sub.- added to another vertical, longitudinal inner major surface in cavity 14b; conductor 15b.sub.+ is connected to sleeve 11.sub.T of test pin 10.sub.T, and conductor 15.sub.- is connected to negative supply pin 10.sub.8.

Holder 1b presents a non-standard thickness substantially greater than the diameter of the button cells. The interior of cavity 14b is accessible from the top of the holder, on the integrated circuit package side.

A cover 6b is hinged to holder 1b about a molded hinge 65 to shut cavity 14b and hold the cells therein in the absence of the integrated circuit package. As shown in FIG. 9, cover 6b is closed downwardly on the top of the holder 1b by a catch and notch arrangement 66. A series of holes 67 run through the longitudinal edges of cover 6b to allow respective pins 20.sub.1 to 20.sub.14 of the package freely through the respective sleeves 11.sub.1 to 11.sub.14 of holder 1b. In practice, a holder, such as holder 1b illustrated in FIGS. 8 and 9, is generally intended for carrying an integrated circuit package with 14, 16, 18, 20 or 22 pins.

FIG. 10 shows a holder 1c carrying an integrated circuit package 2c having two rows of 20 pins 20c.sub.1 to 20c.sub.20 and 20c.sub.21 to 20c.sub.40. Holder 1c is molded out of plastic to a parallelepipedal shape analogous to that of holder 1 depicted in FIG. 1. However, holder 1c offers three square slots 14c.sub.1, 14c.sub.2 and 14c.sub.3 longitudinally aligned between two side-members 12c.sub.1 and 12c.sub.2 and two end cross-members 13c.sub.1 and 13c.sub.2. Slot 14c.sub.3 is in the middle of the holder and separated from the other two slots 14c.sub.1 and 14c.sub.2 by two intermediate cross-members 13c.sub.3 and 13c.sub.4. Each slot 14c.sub.1, 14c.sub.2, 14c.sub.3 is designed to receive a button cell 4.sub.1, 4.sub.2, 4.sub.3 having a diameter substantially smaller in length than a side of the square slot. Only cell 4.sub.2 is shown in FIG. 10. Holder 1c comprises two longitudinal rows of vertical metallic pins 10c.sub.1 to 10c.sub.20 and 10c.sub.21 to 10c.sub.40 protruding from the underside of side-members 12c.sub.1 and 12c.sub.2 and having vertical sleeves 11c.sub.1 to 11c.sub.20 and 11c.sub.21 to 11c.sub.40 standing proud on side-members 12c.sub.1 and 12c.sub.2. Sleeves 11c.sub.1 to 11c.sub.40 are designed to receive tips of pins 20c.sub.1 to 20c.sub.40 of integrated circuit package 2c. Pins 10c.sub.1 and 10c.sub.21 are diagonally opposed across the holder and receive package pins 20c.sub.1 and 20c.sub.21 forming positive and negative supply terminals of the integrated circuit respectively. In an analogous fashion with the embodiment in FIG. 1, right-angled metallic spades 17c.sub.+ and 17c.sub.- are soldered to supply pins 10c.sub.1 and 10c.sub.21 and can be soldered to metallic supply strips 16c.sub.+ and 16c.sub.- extending along outer vertical longitudinal edges of side-members 12c.sub.1 and 12c.sub.2. A rectangular sheet 54c of electrically insulating material is also laid beneath holder 1c such that pins 10c.sub.1 to 10c.sub.40 run through the sheet 54c.

It is assumed hereinafter that cells 4.sub.1, 4.sub.2 and 4.sub.3 are series-connected as shown in FIG. 11F: cells 4.sub.1 and 4.sub.3 carry upwardly extending positive terminals 40.sub.1.sup.+ and 40.sub.3.sup.- and cell 4.sub.2 carries a downwardly extending positive terminal 40.sub.2.sup.+. Two right-angled and resilient metallic connecting plates 5c.sub.1 and 5c.sub.2 are provided to connect cells 4c.sub.1 and 4c.sub.2 and cells 4c.sub.3 and 4c.sub.2 respectively. Plates 5c.sub.1 and 5c.sub.2 include horizontally extending flat portions that pass through the middles of intermediate cross-members 13c.sub.3 and 13c.sub.4 and that extend at least up to the center of slots 14c.sub.1 and 14c.sub.3. Plates 5c.sub.1 and 5c.sub.2 further include vertically extruding flat portions that extend upwards in the vicinity of cross-members 13c.sub.3 and 13c.sub.4 in slots 14c.sub.3 and 14c.sub. 2 respectively. When cells 4.sub.1, 4.sub.2 and 4.sub.3 are inserted in respective slots 14c.sub.1, 14c.sub.2 and 14c.sub.3, as depicted in FIG. 11F, the horizontal flat portions of plates 5c.sub.1 and 5c.sub.2, preferably substantially bent upwardly, come into pressure contact with small negative terminals 40.sub.1.sup.- and 40.sub.3.sup.- of cells 4.sub.1 and 4.sub.3 and carry cells 4.sub.1 and 4.sub.3, whereas the vertical flat portions of plates 5c.sub.1 and 5c.sub.2, preferably substantially bent towards cross-member 13c.sub.2, are pressed against the outer cylindrical metallic circumferences of positive terminals 40.sub.3.sup.+ and 40.sub.2.sup.+ of cells 4.sub.3 and 4.sub.2 respectively.

Cell 4.sub.2 is borne by a cylindrical bottom cap 56 molded from an electrically insulating material. Cap 56 acts as a switch between spare power source 4.sub.1 -4.sub.3 -4.sub.2 and supply pins 10c.sub.1 and 10c.sub.2 in order to bring the spare source into play or not. Cap 56 comprises a circular base against which positive terminal 40.sub.2.sup.+ of cell 4.sub.2 is pressed. An upwardly extending cylindrical wall of cap 56 is castellated to form at least two diametrically opposed cylindrical segments that are resilient towards the center of the cap, or preferably as illustrated in FIG. 10, to form four cylindrical segments 57 diametrically opposed two by two such that the circular metallic circumference of terminal 40.sub.2.sup.+ can be clasped therein. Segments 57 are substantially smaller height-wise than cell 4.sub.2, and cap 56 is substantially equal in outside diameter to the length of the square slot 14c.sub.2 sides. Under these conditions, cap 56 together with cell 4.sub.2 can turn with a slight interference fit between the inside walls of slot 14c.sub.2, and the small vertical flat portion of connecting plate 5c.sub.2 under the effect of its own deflection comes alternately into mechanical contact with one of insulating segments 57 to disconnect terminal 40.sub.2.sup.+ of cell 4.sub.2 from terminal 40.sub.3.sup.- of cell 4.sub.3, and thus switch off the spare power supply, and alternately into electrical contact with the circular metallic circumference of terminal 40.sub.2.sup.+ to switch the spare power supply on and thereby series-connect cells 4.sub.1, 4.sub.2 and 4.sub.3 across pins 10c.sub.1 and 10c.sub.21. These disconnection and connection operations are in fact performed by rotating cap 56 through approximately one quarter of a turn, use being made therefor of a lever 58 projecting radially outwards from one of segments 57. A resilient free end of lever 58 protrudes substantially from holder 1c over end cross-member 13c.sub.2 and can be slotted either in an oblique groove 59S close to pin 10c.sub.21 in cross-member 13c.sub.2, or in a substantially transverse groove 59H in cross-member 13c.sub.2 between the mid-point thereof and groove 59S. Grooves 59S and 59H constitute stop-notches to halt rotation of cap 56 and respectively correspond to emplacements of segment 57 diametrically opposite lever 58 in which segment 57 is separated from connecting plate 5c.sub.2 and is in mechanical contact with connecting plate 5c.sub.2.

As shown in FIG. 10, holder 1c is associated with a removable cover 9 to permit easy connection and disconnection, without any soldering, of pins 20c.sub.1 to 20c.sub.40 of integrated circuit package 2c with respect to sleeves 11c.sub.1 to 11c.sub.40 of holder 1c on the one hand, and to hold cells 4.sub.1, 4.sub.2 and 4.sub.3 in place inside holder 1c particular when there is no package 2c.

Cover 9 consists of a molded plastic rectangular frame having length and width substantially smaller than holder 1c and formed of two side-members 92.sub.1 and 92.sub.2 and two end cross-members 93.sub.1 and 93.sub.2. Two intermediate cross-members 93.sub.3 and 93.sub.4 split cover into three square slots 94.sub.1, 94.sub.3 and 94.sub.2 that match slots 14c.sub.1, 14c.sub.3 and 14c.sub.2. Cross-members 93.sub.1 to 93.sub.4 assume an upwardly convex cross-section, e.g. a trapezoidal cross-section as shown in FIG. 10, such that only side-members 92.sub.1 and 92.sub.2 rest on holder 1c, i.e. on side-members 12c.sub.1 and 12c.sub.2 when cover 9 lies in place on holder 1c. Cover 9 is then secured in place between thin longitudinal sidewalls 121 and 122 running along the edge of holder 1c, extending side members 12c.sub.1 and 12c.sub.2 upwards and having right-angled portions at the four corners of the holder. In the embodiment shown in FIG. 10, two resilient locking lugs 98.sub.1 and 98.sub.2 extend vertically and downwardly from the middle of end cross-members 93.sub.1 and 93.sub.2 and carry pairs of outwardly upper and lower horizontal ribs 981.sub.1 and 981.sub.2 and 982.sub.1 and 982.sub.2 to cooperate with inwardly extending central vertical grooves 130.sub.1 and 130.sub.2 and horizontal rectangular apertures 131.sub.1 and 131.sub.2 embodied in cross-members 13c.sub.1 and 13c.sub.2 respectively. The distance between upper rib 982.sub.1, 982.sub.2 and lower rib 981.sub.1, 981.sub.2 on each lug 98.sub.1, 98.sub.2 is equal to half the height of end cross-members 13c.sub.1 and 13c.sub.2. Locking lugs 98.sub.1 and 98.sub.2 slide in grooves 130.sub.1 and 130.sub.2 inside the slots 14c.sub.1 and 14c.sub.2, and the pairs of ribs 981.sub.1 -982.sub.1 and 981.sub.2 -982.sub.2 clamp around central portions of cross-members 13c.sub.1 and 13c.sub.2 above apertures 131.sub.1 and 131.sub.2 when cover 9 is pressed down on holder 1c in order to lock the cover and holder together, as depicted in FIG. 12.

Cover side-members 92.sub.1 and 92.sub.2 carry two series of square-section vertical holes 91.sub.1 to 91.sub.20 and 91.sub.21 to 91.sub.40 intended to receive sleeves 11c.sub.1 to 11c.sub.20 and 11c.sub.21 to 11c.sub.40 of holder 1c from underneath and pins 20c.sub.1 to 20c.sub.20 and 20c.sub.21 to 20c.sub.40 of package 2c from above. As shown in detail in FIG. 12, each sleeve, such as sleeve 11c.sub.2, is made up of two electrically conductive vertical reeds, in this case parallel to sidewalls 121 and 122, having a length less than that of holes 91.sub.1 to 91.sub.40. When cover 9 and holder 1c are assembled by pushing cover 9 downwards, lower ribs 982.sub.1 and 982.sub.2 of lugs 98.sub.1 and 98.sub.2 penetrate firstly into apertures 131.sub.1 and 131.sub.2 respectively, and the reeds of sleeves 11.sub.1 to 11.sub.40, with a slight interference fit, enter chamfered holes 91.sub.1 to 91.sub.40. Outer longitudinal edges of side-members 92.sub.1 and 92.sub.2 are vertical and slide between side walls 121 and 122. Package 2c then slips over cover 9 such that pins 20c.sub.1 to 20c.sub.40 vertically enter from the upper chamfered openings into holes 91.sub.1 to 91.sub.4 and slide in between the reeds of sleeves 11c.sub.1 to 11c.sub.40 respectively. Package 2c is then sharply pressed downwards such that upper ribs 981.sub.1 and 981.sub.2 engage in apertures 131.sub. 1 and 131.sub.2, and lower ribs 982.sub.1 and 982.sub.2 drop below cross-members 13c.sub.1 and 13c.sub.2. At this stage, the convexity of cover cross-members 91.sub.1 to 93.sub.4 decreases and cross-members 93.sub.1 to 93.sub.4 tend to flatten out whereby side-members 92.sub.1 and 92.sub.2 move further apart and come into pressure contact with sidewalls 121 and 122 running around the holder. As side-members 92.sub.1 and 92.sub.2 become pushed apart, and reeds of sleeves 11c.sub.11 to 11c.sub.40 are substantially pressed outwards thereby fixedly pinching the tips of pins 20c.sub.1 to 20c.sub.40 such that effective mechanical and electrical contacts therewith are made, without relying on soldering. Furthermore, cover 9 and package 2c are fixedly held superposed on holder 1c.

When package 2c is withdrawn, a special forked tool, or more simply a screw-driver, can be used to free lower ribs 982.sub.1 and 982.sub.2 upwards from underneath end cross-members 13c.sub.1 and 13c.sub.2 whereupon lower ribs then become engaged in apertures 131.sub.1 and 132.sub.2. The upward movement of lugs 98.sub.1 and 98.sub.2 is eased by the natural resilience of cover cross-members 93.sub.1 and 93.sub.4 that become more convex in shape, and the natural resilience of holder sidewalls 121 and 122 that become more vertical. Package 2c can be removed without necessarily removing the cells since cover 9 is still locked to holder 1c by means of lower ribs 982.sub.1 and 982.sub.2 in apertures 131.sub.1 and 131.sub.2. The withdrawal of one or several cells is achieved by pulling cover 9 upwards so as to free lower ribs 982.sub.1 and 982.sub.2 from apertures 131.sub.1 and 131.sub.2.

In a further embodiment of means for locking cover 9 to holder 1c, lugs 98.sub.1 and 98.sub.2 and the groove and aperture arrangements 130.sub.1 -131.sub.1 and 130.sub.2 -131.sub.2 are replaced by two vertical cylindrical lugs 99 subjacent to cross-members 93.sub.1 and 93.sub.2, and by two vertical cylindrical holes 132 in the middle of cross-members 13c.sub.1 and 13c.sub.2, as shown in FIG. 13. Each lug 99 carries a diametral vertical slit 990 that is perpendicular to cross-member 93.sub.1, 93.sub.2 and a downwardly converging conical end tip 999 having top-side flange 992. As shown in FIGS. 14A to 14E, a locking ring 133 is added to an upper end of each hole 132 and fixed therein. Ring 133 comprises an inner annular groove 134 having a conical lower portion. Hole 132 can be blind or open out at 135 with a diameter smaller than most of the remaining hole such that a cylindrical chamber 136 is created beneath ring 133. Provided in chamber 136 is a washer 137 having a chamfered upper portion. The diameters of bores in the ring 133 and washer 137 are smaller than the diameter of tip 991 and substantially equal to the width of the tip when lug arms separated by slit 990 are pressed against each another, as depicted in FIGS. 14A and 14C. In other embodiment, the cross-section of members 99, 133 and 137 and bores therein are square or polygonal.

When the time comes to lock cover 9 on holder 1c, once cells 4.sub.1 to 4.sub.3 have been inserted in slots 14c.sub.1 to 14c.sub.3 and prior to placing package 2c onto cover 9, flanges 992 of two lugs 99 are engaged in inner annular grooves 134 of rings 133 as shown in FIG. 14E. After insertion of pins 20c.sub.1 to 20c.sub.40 in sleeves 11c.sub.1 to 11c.sub.40, a second downward pressure brings the arms of tips 991 together by a downward movement into the bores in rings 133, as shown in FIG. 14A. Then flanges 992 spread out beneath rings 133, as shown in FIG. 14B. At this stage, the pins of package 2 are locked in the sleeves of holder 1c.

A third downward pressure on package 2c has the result that tips 991 become engaged in washers 137, as shown in FIG. 14C. The opposed deflections of the arms on either side of slit 990 of each lug 99 enable respective flange 932 to make lug 99 momentarily integral with respective washer 137. Once package 2c has been released, the elastic expansion of cross-members 93.sub.1 to 93.sub.4 of the cover lifts lugs 99 upwards bringing washers 137 with them through their sliding action in chambers 136 until the washers butt against rings 133, as shown in FIG. 14D. Washers 137 fall back to the bottom of chamber 136 and tips 931 then move up inside rings 133 until flanges 992 enter inner annular grooves 134 when slits 990 expand, as shown in FIG. 14E. Package 2 can then be withdrawn from cover 9.

Again referring to FIG. 10, cover 9 comprises two resilient and electrically conductive contact reeds 95.sub.+ and 95.sub.-, and a clamping diode D.sub.1. Reeds 95.sub.+ and 95.sub.- longitudinally extend away from the mid-points of cross-members 93.sub.1 and 93.sub.2 into slots 94.sub.1 and 94.sub.2 where they come into pressure contact with positive terminal 40.sub.1.sup.+ of cell 4.sub.1 and negative terminal 40.sub.2.sup.- of cell 4.sub.2 respectively, as shown in FIG. 11F.

The diode D.sub.1 is fully embedded in cross-member 93.sub.1 between hole 91.sub.1, and reed 95.sub.+. An electrical conductor is partly embedded in cross-member 93.sub.1, connects reed 95.sub.+ to an anode of diode D.sub.1, and offers a bend 91.sub.T emerging outwardly from the middle of cross-member 93.sub.1, as shown in FIGS. 10 and 15. Bend 91.sub.T serves as a test terminal, like pin 10.sub.T in FIG. 1.

A cathode of diode D.sub.1 is connected to an electrical conductor 138.sub.1 embedded in cross-member 93.sub.1. Conductor has a downwardly vertically extending flat tip 139.sub.1 emerging from the underside of cross-member 93.sub.1 in the vicinity of hole 91.sub.1, as shown in FIGS. 10 and 15. Likewise, contact reed 95.sub.- is connected to an electrical conductor 138.sub.2 embedded in cross-member 93.sub.2 and having a downwardly vertically extending flat tip 139.sub.2 emerging from the underside of cross-member 93.sub.2 close to hole 91.sub.21, as shown in FIG. 16. Tip-ends 139.sub.1 and 139.sub.2 are intended respectively to come into mechanical and electrical contact with contact plates 111.sub.1 and 111.sub.2 on sleeves 11c.sub.1 and 11c.sub.2 of supply pins 10c.sub.1 and 10c.sub.21, as shown in FIG. 12. As can be seen in FIG. 17, contact plate 111.sub.1, 111.sub.2 is cut out in one of the two reeds of sleeve 11c.sub.1, 11c.sub.2 just above supply pin 10c.sub.1, 10c.sub.21 and is substantially deflected upwards. When cover 9 is inserted over holder 1c between surrounding walls 121 and 122, tip-ends 139.sub.1 and 139.sub.2 press on contact plates 111.sub.1 and 111.sub.2 respectively, and simultaneously therewith, contact reeds 95.sub.+ and 95.sub.- press on terminal 40.sub.1.sup.+ of cell 4.sub.1 and on terminal 40.sub.2.sup.- of cell 42 respectively. Terminal 40.sub.1.sup.+ of cell 4.sub.1 is connected to positive supply pin 10c.sub.1 through test terminal 91.sub.T, diode D.sub.1, conductor 138.sub.1, tip-end 139.sub.1 of conductor 138.sub.1 and contact plate 111.sub.1 of sleeve 11c.sub.1. Terminal 40.sub.2.sup.- of cell 4.sub.2 is connected to negative supply pin 10c.sub.21 through conductor 138.sub.2, tip-end 139.sub.2 of conductor 138.sub.2 and contact plate 111.sub.21 of sleeve 11c.sub.21.

The structure of holder 1c such as described above can be adapted to the shape, the mutual configuration of the terminals on each cell and the dimensions, such as the thickness, of the cells. Various adaptations are given as examples in FIGS. 11A to 11H. In FIG. 11E, holder 1c contains three button cells each equipped with a small circlar metallic surface as a positive terminal, analogous with negative terminals 40.sub.1.sup.- to 40.sub.3.sup.- of cells 4.sub.1 to 4.sub.3, and a large cylindrical metallic surfaces as a negative terminal, analogous with positive terminals 40.sub.1.sup.+ to 40.sub.3.sup.+ of cells 4.sub.1 to 4.sub.3 ; in this case, cap 56 acting as a switch receives the negative terminal of a cell inserted in slot 14c.sub.1, and connecting plates 5c.sub.1 and 5c.sub.2 are turned around through 180.degree.; grooves 59S and 59H are also provided in cross-member 13c.sub.1 to receive lever 59, as indicated in FIG. 10. FIGS. 11G and 11H respectively correspond to FIGS. 11E and 11F wherein each cell is replaced by two button cells half the thickness of the cells in FIGS. 11E and 11F; in this case, right-angle connecting plates 5c.sub.2, as in FIG. 11E, and 5c.sub.1, as in FIG. 11F, are respectively replaced by connecting plates 5c'.sub.2 and 5c'.sub.1 each having a vertical portion running through corresponding intermediate cross-member 13c.sub.4 and 13c.sub.3, and each having a horizontal short upper portion and a horizontal long lower portion at respective ends of the vertical portion to be pressed into contact on the bottom and top of the terminals on the upper and lower slim-line cells in adjacent slots 14c.sub.2 and 14c.sub.3, 14c.sub.1 and 14c.sub.3, respectively. Lastly, holders are shown in FIGS. 11A to 11D with just two slots 14c.sub.1 and 14c.sub.2 each housing one or two cells arranged respectively in a fashion analogous to the end cells in FIGS. 11E to 11H.

The structures of holder 1c and cover 9 can be substantially modified. Each of slots 14c.sub.1 to 14c.sub.3 and 94.sub.1 to 94.sub.3 can carry a longitudinally or transversally extending bar or can include a downwardly molded bottom in order to create cavities for the cells. The spare power source switch can consist of a longitudinal or vertical slide with metallized ends in lieu of cap 56.

A description now follows of another embodiment mode of an integrated circuit package holder containing, over and above a spare power source with two slim-line cells 4.sub.1 and 4.sub.2, a circuit 7 for monitoring the charge in the spare source with a view to indicating any discharge in the spare source with respect to a predetermined voltage threshold.

A first embodiment of holder 1 in accordance with this other embodiment mode is illustrated in FIG. 18. Holder 1 is shaped in a generally similar fashion to the holder already described in reference to FIG. 1, although in another embodiment, the holder can be analogous to holder 1c shown in FIG. 10.

Two button cells 4.sub.1 and 4.sub.2 are horizontally laid one above the other in first slot 14.sub.1, positive terminal 40.sub.2.sup.+ of cell 4.sub.2 being placed over negative terminal 40.sub.1.sup.- of cell 4.sub.1. Positive terminal 40.sub.1.sup.- of lower cell 4.sub.1 is connected to supply pin 10.sub.1 of the holder via pan-shaped conductive contact reed 15.sub.30 and diode D.sub.1. Test pin 10.sub.T is done away with. Terminal 40.sub.1.sup.+ is also connected via an electrical conductor 15.sub.T to a test terminal TT of monitoring circuit 7 that is lodged in second slot 14.sub.2. Conductor 15.sub.T is preferably embedded in the holder and runs around slot 14.sub.1 through cross-member 13.sub.1, side-member 12.sub.2 and central cross-member 13.sub.0.

Connecting plate 5 in FIG. 1 is replaced by an analogous connecting plate comprising only the longitudinal half-portion between contact end 52.sub.1 and the two downwardly extending lugs 51. Horizontal end 52.sub.1 is pressed against negative terminal 40.sub.2.sup.- of upper cell 4.sub.2 and pushes cells 4.sub.1 and 4.sub.2 against contact reed 15.sub.+ when both lugs 51 are plugged in holes 131 of central cross-member 13.sub.0. Holes 131 are metallized in this case. Holes 131 are connected to the ground referred negative supply pin 10.sub.15 of holder 1 and to a grounding terminal GT of monitoring circuit 7 via an electrical conductor 15.sub.G preferably embedded in the holder and running around slot 14.sub.2 through cross-member 13.sub.0 and side-member 12.sub.2.

With the exception of the modifications to the holder regarding the insertion of monitoring circuit 7, all the other holder members such as pins 10.sub.1 to 10.sub.28, sleeve 11.sub.1 to 11.sub.28, conductive strips 16.sub.+ and 16.sub.-, conductive right-angled spades 17.sub.+ and 17.sub.- and electrically insulating sheet 54 in FIG. 18 are analogous to those described in reference to FIG. 1, respectively.

The block diagram of monitoring circuit 7 is shown in FIG. 19. Circuit 7 essentially comprises a voltage controlled oscillator tuned to a variable frequency within an audible frequency range, a controlling circuit 71 controlling oscillator 70, and a display circuit 72.

Oscillator 70 comprises a trigger 701 associated with a feedback resistor 702 and a variable capacitor in the form of a varicap 703 connected to terminal GT. An input of the oscillator consists of a terminal 704 common to resistor 702 and to varicap 703. Terminal 704 is connected to test terminal TT and hence to positive terminal 40.sub.1.sup.+ of spare source 4.sub.1 -4.sub.2 through a resistor 73 connected in series with a forward biased diode 74. The signal frequency appearing at an output 705 from trigger 701 is inversely proportioned to the RC parameter of the constant resistance of resistor 702 and the variable capacitance of varicap 703, and is therefore inversely proportional to the voltage applied to test terminal TT.

Controlling circuit 71 consists essentially of an RS type flip-flop 711. An input R of flip-flop 711 is connected to a zero resetting terminal RT of circuit 7. Another input S of flip-flop 711 is connected to an enabling terminal ET of circuit 7. One output Q of flip-flop 711 is connected to a triggering input 706 of trigger 701. Terminals ET and RT as well as an output terminal OT of circuit 7 are connected to a microprocessor (not shown) mounted on printed circuit board 3 via respective electrical conductors 15.sub.E, 15.sub.R and 15.sub.O embedded in holder 1 at second slot 14.sub.2 and via respective additional pins 10.sub.E, 10.sub.R and 10.sub.O, as shown in FIG. 18. The microprocessor or another equivalent circuit makes it possible to question the monitoring circuit to indicate discharge of the spare source. This inquiry is carried out when the microprocessor does not perform other priority tasks, or periodically depending on the organization of the other electronic circuits mounted on the printed circuits board.

The microprocessor inquiry is transmitted in the form of a transient negative pulse to terminal RT in order to reset flip-flop 711. More periodically, a transient negative pulse is fed to terminal ET by the microprocessor in order to enable trigger 701 by feeding a logic state "1" to input 706. If the spare source voltage on terminal TT is higher than the predetermined threshold voltage, typically equal to 2.5 volts for two cells each working normally with 1.5 volt, oscillator 70 stays off and no oscillating signal is detected by the microprocessor at the output OT. On the other hand, if the voltage on the test terminal TT is lower than the predetermined threshold, which would correspond to discharge in the two spare source cells, an audible frequency oscillating signal is delivered by terminal 705 of oscillator 70 to the terminal OT and energizes display circuit 72. A warning is given by circuit 72 to the effect that the spare source will soon be inoperative, where the predetermined voltage threshold is chosen substantially higher than the spare source minimum withstand voltage. The state of the terminal RT is not modified by the microprocessor in response to the oscillating signal. In the opposite case, the microprocessor delivers a transient pulse on the terminal RT to zero reset flip-flop 711 that cuts out oscillator 70, thereby avoiding any un-timely discharge from spare source 4.sub.1 -4.sub.2.

Display circuit 72 comprises an electro-acoustic transducer 721 such as a miniature loudspeaker in the form of a piezoelectric bar buzzer. Terminals 722 and 723 of transducer 721 are connected to the grounding terminal GT and, via an inverter 724, and to terminals 705 and OT respectively. Circuit 70 can, on option, carry a display device 725 such as a liquid crystal or LED block. The display device is then connected between the output 705 of oscillator 70 and the terminal OT connected to inputs of inverter 724.

Monitoring circuit 7 also comprises other components, such as bias resistors 712, 713 and 726 respectively connected to the terminals RT, ET and OT and raised to a positive potential by a common terminal BT. The terminal BT is connected to board 3 via an electrical conductor 15.sub.B embedded in holder 1, as depicted in FIG. 18.

Monitoring circuit 7 can be manufactured in the form of an integrated circuit enclosed in a package or in a hybrid form of discrete components mounted on a small printed circuit board. FIGS. 20, 21 and 22 illustrate an embodiment of the monitoring circuit 7 package composed of an electrically insulating discord base member 75 and a cylindrical metal or plastic cap 76. A substrate 77 for integrated or discrete monitoring circuit 7 is bonded to an inside surface of base member 75. Six small vertical conductive prongs constitute the terminals GT, OT, ET, BT, RT and TT and are plugged into respective metallized holes in a moulded bottom of slot 14.sub.2 in holder 1. Slot 14.sub.2 forms here a circular receptacle of package 75-76 having a typical diameter of 2.5 cm. The aforesaid metallized holes from the ends of conductors 15.sub.G, 15.sub.O, 15.sub.E, 15.sub.B, 15.sub.R and 15.sub.T. In another embodiment, the prongs of package 75-76 related to the terminals OT, ET, BT and RT replace pins 10.sub.O, 10.sub.E, 10.sub.B and 10.sub.R and pass through the bottom of cavity 14.sub.2. Holes are provided in part of the circular circumference of cap 76 for the display device 725, such as light emitting diodes shown in FIGS. 21 and 22.

Piezoelectric buzzer 721 can form a major portion of the top of cap 76 and carry terminals 722 and 723 in the form of wires lodged in the monitoring circuit package and soldered to substrate 77, as shown in FIGS. 20 and 21. In a further embodiment shown in FIG. 18, buzzer 721 containing inverter 724 is laid flat on an adhesive strip 780 that is integral with a U-shaped clip 78. Downwardly folded tabs 781 on clip 78 are snapped over the lateral ends of integrated circuit package 2. Terminals 722 and 723 of buzzer 721 are made up of flexible wires soldered or pinched onto pins 10.sub.15 and 10.sub.0 of holder 1.

In a further embodiment depicted in FIG. 23, a common controlling circuit 71 monitors a greater number of spare power sources, e.g. six SPS.sub.1 to SPS.sub.6. Each power source SPS.sub.1 to SPS.sub.6 is lodged in first slot 14.sub.1 of a respective integrated circuit package holder 1.sub.1 to 1.sub.6 analogous with holder 1 shown in FIG. 18. Second slot 14.sub.2 in each of holders is in the form of a cavity including a hybrid or integrated monitoring circuit 7.sub.1 to 7.sub.6 comprising an oscillator 70.sub.1 to 70.sub.6, a resistor 73.sub.1 to 73.sub.6 and a diode 74.sub.1 to 74.sub.6 all analogous with those described with reference to FIG. 19, respectively, as well as other components 727.sub.1, 727.sub.6, 728.sub.1 to 728.sub.6 and 729.sub.1 to 729.sub.6. The hybrid or integrated circuit further comprises a display device 725.sub.1 to 725.sub.6, such as light emitting diodes or a liquid crystal block, interconnected between the positive terminal BT and output 705.sub.1 to 705.sub.6 from oscillator 70.sub.1 to 70.sub.6 through an inverter 727.sub.1 to 727.sub.6 and a resistor 728.sub.1 to 728.sub.6. A non-inverting component 727'.sub.1 to 727'.sub.6 and the display device 725.sub.1 to 725.sub.6 can be suitably series-connected to the grounding terminal GT as in another embodiment shown in FIG. 24.

One of the holders 1.sub.1 to 1.sub.6, such as the holder 1.sub.1 related to circuit 7.sub.1 shown in FIG. 15, further includes controlling circuit 71 with RS flip-flop 711, piezoelectric buzzer 721, two switches 714 and 715 and two bias resistors 716 and 717. Output Q of flip-flop 711 is connected to triggering inputs 706.sub.1 to 706.sub.6 of oscillators 70.sub.1 to 70.sub.6. Terminal 723 of common buzzer 721 is connected to outputs 705.sub.1 to 705.sub.6 of oscillators 70.sub.1 to 70.sub.4 via switches 729.sub.1 to 729.sub.6. Switches 729.sub.1 to 729.sub.6, 714 and 715 are CMOS-technology gates. The various connections between the six circuits 7.sub.1 to 7.sub.6 carried by the holders 1.sub.1 to 1.sub.6 are made via holder pins and conductive strips on printed circuit board 3.

The monitoring circuit shown in FIG. 23 operates in the following manner. A transient negative pulse fed to the terminal RT resets flip-flop 711 which closes gates 714 and 715. An enabling pulse fed to the terminal ET then changes the state of flip-flop 711 that enables triggers 701.sub.1 to 701.sub.6 of oscillators 70.sub.1 to 70.sub.6 and opens gates 714 and 715. As a second input on gate 714 is connected to the positive voltage terminal BT across resistor 716, an output of gate 714 applies a positive voltage to the inputs of gates 729.sub.1 to 729.sub.6 and to another input of gate 715. Other inputs of gates 729.sub.1 to 729.sub.6 are respectively connected to output 705.sub.1 to 705.sub.6 of oscillators 70.sub.1 to 70.sub.6. If none of the spare power source SPS.sub.1 to SPS.sub.6 produces a voltage lower than the predetermined voltage threshold, gates 729.sub.1 to 729.sub.6 and 715 stay off and the voltage on the output terminal OT goes unchanged.

Should any of the spare power sources SPS.sub.1 to SPS.sub.6 deliver a voltage lower than the predetermined voltage threshold, signifying then that the source is being discharged, an audible frequency signal is delivered from respective output 705.sub.1 to 705.sub.6 of the corresponding oscillator 70.sub.1 to 70.sub.6. The audible frequency signal energizes the corresponding display device 725.sub.1 to 725.sub.6 and, in synchronism with the audible frequency, opens the corresponding gate 729.sub.1 to 729.sub.6. The positive voltage fed by gate 714 activates buzzer 721 via the corresponding gate 729.sub.1 to 729.sub.6. In view of the buzzer 721 impedance, the output OT of gate 715 delivers ground referred voltages in synchronism with the audible frequency. The alternating signal on the output OT is then processed by the microprocessor and indicates a voltage abnormality of one of the six spare power sources SPS.sub.1 to SPS.sub.6.

In a further embodiment, a monitoring circuit comprises all the circuits 7.sub.1 to 7.sub.6 in FIG. 23 and is fully carried on the same holder, such as the holder related to circuit 7.sub.1, which comprises then five test pins connected via the printed circuit board to the positive terminals of the power sources SPS.sub.2 to SPS.sub.6 included in the other five holders.

In a further embodiment, the integrated or hybrid ciruit package 75-76 in cavity 14.sub.2 of holder 1 shown in FIGS. 18 and 20 to 22 also includes an inhibiting circuit 8. Circuit 8 inhibits a predetermined function of the integrated circuit housed in package 2 when the voltage of the main power source MPS disappears. If the integrated circuit in package 2 is a memory, the predetermined function to inhibit is a writing authorization in the memory, for example.

As shown in FIG. 25, inhibiting circuit 8 comprises two npn transistors 80 and 81 having emitters connected to the grounding terminal GT. Collectors of transistors 80 and 81 are respectively connected across resistors 82 and 83 to a common terminal of clamping diodes D.sub.1 and D.sub.2 already mentioned with reference to FIG. 3. The collector of transistor 80 is connected to a base of transistor 81. A base of transistor 80 is connected to the positive voltage terminal MPS.sub.+ of the main power source MPS to be monitored, via a resistor 84 and an additional pin (not shown) of holder 1. The collector of transistor 81 is connected to the terminal BT across a diode 85 and a resitor 86. An anode of diode 85 and a terminal of resistor 86 form a common terminal 86 to be connected to a function inhibiting input of the integrated circuit in package 2, across an additional pin (not shown) of holder 1.

When the main power source MPS delivers a voltage normally, the positive voltage of terminal MPS.sub.+ turns on first transistor 80 and turns off second transistor 81. The voltage on the collector of transistor 81 is positive, which produces no active ground to terminal 87.

When the main power source voltage disappears, spare source 4.sub.1 -4.sub.2 takes over from the main source MPS by applying a supply voltage across diode D.sub.1. On the other hand, the disappearance of the positive voltage on the terminal MPS.sub.+ turns off transistor 80. The positive voltage on the collector of transistor 80 turns on second transistor 81, and diode 85 becomes conductive. An active ground is thus present at terminal 87 that controls inhibition of the predetermined function in the integrated circuit of package 2.