Integrated circuit package holder

An integrated circuit package holder comprises a recess for a receipt of a removable spare power source such as two miniature cells to be interconnected between two pins of the holder into which two package supply pins are plugged. The holder can further contain, in a hybrid or integrated form, a circuit for detecting a voltage across spare source terminals that is lower than a predetermined discharge threshold, and a circuit for inhibiting a predetermined function in the integrated circuit when a main power source voltage between the supply pins disappears. A cover inserted between the holder and the package can be provided to connect the package pins to the holder pins without soldering, the cover and the package being locked to the holder by means of single pressures.

BACKGROUND OF THE INVENTION 
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. 
OBJECTS OF THE INVENTION 
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. 
SUMMARY OF THE INVENTION 
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.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
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.