Datasheet M4T32-BR12SH1, M4T28-BR12SH1, M4T32-BR12SH6 Datasheet (SGS Thomson Microelectronics)

TIMEKEEPER SNAPHAT (Battery & Crystal)

■ Provides Ba ttery Backup Power for Non -Volatile

TIMEKEEPE Rs and Controllers in the
SNAPHAT SOIC Package

■ Removable Battery Avoids Heat Associated

with Surface Mount Process

■ Snaps Directly onto Surface-Mounted

SNAPHAT SOIC

■ Choice of Battery Capacities

– M4T28-BR12SH = 48 mAh
– M4T32-BR12SH = 120 mAh

■ Keyed Insertion to Insure Proper Assembly

■ Removable for Replacement and Proper

Disposal

■ Available in Tubes or Tape & Reel

■ For Use with the 28 and 44 pin SOIC Versions

of the TIMEKEEPER Product Families

M4TXX-BR12SH

SNAPHAT (SH)

Battery & Crystal

Figure 1. Logic Diagram

DESCRIPTION

The M4Txx-BR12SH SNAP HAT top is a detach­able lithium power source for ST’s non-volatile
TIMEKEEPER surface mount SOIC (MH) pack­age (28 and 44 pin).

The SNAPHAT top cont ains both the battery and
crystal and is designed to be "snapped on" after
the SOIC is surface mounted on the PC board.
Thus the two piece solution avoids the battery and
crystal from having to be exposed to the high tem­peratures of the surface mount process.

X1 X2

SNAPHAT

V

BAT–VBAT+

AI02528

1/7November 1999

M4TXX-BR12SH

MECHANICAL INFORMATION

Electrical connection to the SOIC is made through
four pins that connect to the four press fitted sock­ets at each end of the SOIC. Critical contact
points between the pins and sockets are gold-plat­ed to resist oxidation. Internally, each socket con­tains six independent contact fingers to form
redundant connections between the two compo­nents. These sockets were designed with high
point contact force to provide the lowest possible
contact resistance. The SNAPHAT top also incor­porates four molded-in retaining clips which hold
onto the ends of the SOIC insuring mechanical
and electrical connection even under severe me­chanical shock and vibration. The combined SOIC
and SNAPHAT assembly can sustain shock levels
in excess of 100 g without separating. This pack­age also passes variable frequency testing in ac­cordance with MIL-STD-883, method 2007.2,
condition A.

Figure 2 illustrates the affect of repeated insertion
and extraction of the SNAPHA T top to the SOIC.
The force required to extract the SNAPHAT, and
then to re-insert it, reduces each time. After three
or four extractions, though, the reduction starts to
become unnoticeable, and the force required
remains at a fairly constant figure. Typically,
though, the SNAPHAT will only need to be
extracted and re-inserted once in its lifetime.

BATTERY CHARACTERISTICS

Figure 3 illust rates the lithi um coin cell disc harge
rate for a given load. This demonstrates the char-

Table 1. Description

Parameter Value

Operating
Temperature

Storage
Temperature

Nominal Crystal
Frequency

Load Capacitance 12.5 pF
Nominal

Battery Voltage
Nominal

Battery Capacity
Battery Chemistry Li(CF)x

1 = 0 to 70 °C
6 = –40 to 85 °C

–40 to 85 °C

32.768 kHz

2.8 V

48 mAh M4T28
120 mAh M4T32

acteristically flat voltage level supplied by t he ba t­tery until very near the end of its life. These
discharge levels have been great ly acc ele rated in
comparison to the normal, actual usage.

UL RECOGNITION

The M4Txx-BR12SH has been recognized by Un­derwriters Laboratories under their Component
Recognition Program and carries U.L. File Num­ber E89556.

Figure 2. SNAPHAT Insertion/Extraction Forces

20

7.5

Force (pounds)

2/7

5

12.5

10

7.5

5

2.5

0

123

Average Insertion Force
Average Extraction Force

45

Number of Extractions

6

7

98

10

AI02526

Figure 3. Batt ery D is cha rge Rates

LOAD CHARACTERISTICS Temp: 20˚C

3.5

3.0

2.5

M4TXX-BR12SH

2.0

Voltage (V)

1.5

1.0
0

LOAD CHARACTERISTICS Temp: 20˚C

3.5

3.0

2.5

2.0

Voltage (V)

1.5

1.0
0

15kΩ 30kΩ

200 400 600 1200 1600 1800

15kΩ 30kΩ 50kΩ 100kΩ

1000 2000 3000 4000 5000 6000

800 1000 1400 2000

Duration (hrs.)

(A)

Duration (hrs.)

(B)

100kΩ

AI02519

BATTER Y LI FE

For information on Data Retention Life and Battery
Storage Life, please refer to the Application Note
AN1012.

GENERAL NOTES

To remove the SNAPHAT top for replacement, a
DIP/IC extractor tool should be used.

Caution: To avoid draining battery do NOT place
SNAPHAT pins in a conductive foam.

Caution: To avoid damaging SNAPHAT s ockets
do NOT wave solder SOIC.

For battery disposal information, see on the web at

www.rayovac.com.

Figure 4. DIP Extractor Tool

AI02527

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M4TXX-BR12SH

Table 2. Ordering Information Scheme

Example: M4T28-BR12 SH 1

Product Family

M4T = SNAPHAT Battery & Crystal

Battery Voltage & Capacity

28-BR12 = BR1225, 3 V, 48 mAh
32-BR12 = BR1632, 3 V, 120 mAh

Package

SH = SNAPHAT

Temperature Range

1 = 0 to 70 °C
6 = –40 to 85 °C

For further information on any aspect of this dev ice, please contact the S TMicroelec tronics Sales Office
nearest to you.

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M4TXX-BR12SH

Table 3. M4T28-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 48 mAh Battery & Crystal,
Package Mechanical Data

Symb

Typ Min Max Typ Min Max

A 9.78 0.385
A1 6.73 7.24 0.265 0.285
A2 6.48 6.99 0.255 0.275
A3 0.38 0.015

B 0.46 0.56 0.018 0.022

D 21.21 21.84 0.835 0.860

E 14.22 14.99 0.560 0.590
eA 15.55 15.95 0.612 0.628
eB 3.20 3.61 0.126 0.142

L 2.03 2.29 0.080 0.090

mm inches

Figure 5. M4T28-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 48 mAh Battery & Crystal,
Package Outline

A2

A3

L

eA

D

A1

A

B

eB

E

SHTK-A

Drawing is not to scale.

5/7

M4TXX-BR12SH

Table 4. M4T32-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal,
Package Mechanical Data

Symb

Typ Min Max Typ Min Max

A 10.54 0.415
A1 8.00 8.51 0.315 0.335
A2 7.24 8.00 0.285 0.315
A3 0.38 0.015

B 0.46 0.56 0.018 0.022

D 21.21 21.84 0.835 0.860

E 17.27 18.03 0.680 0.710
eA 15.55 15.95 0.612 0.628
eB 3.20 3.61 0.126 0.142

L 2.03 2.29 0.080 0.090

mm inches

Figure 6. M4T32-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal,
Package Outline

A2

A3

L

eA

D

A1

A

B

eB

E

SHTK-A

Drawing is not to scale.

6/7

M4TXX-BR12SH

If you have any questions or suggestions concerning the matters raised in this document, please send
them to the following electronic mail addresses:

[e-mail]
[e-mail]

Please remember to include your name, company, location, telephone num ber and fax number.

(for application support)
(for general enquiries)

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