STMICROELECTRONICS M4T28

M4TXX-BR12SH
TIMEKEEPER SNAPHAT (Battery & Crystal)
■
Provides Battery Backup Power for Non-Volatile
TIMEKEEPERs 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
DESCRIPTION
The M4Txx-BR12SH SNAPHAT 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 contains 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.
SNAPHAT (SH)
Battery & Crystal
Figure 1. Logic Diagram
X1
X2
SNAPHAT
VBAT–
VBAT+
AI02528
November 1999
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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 SNAPHAT 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 illustrates the lithium coin cell discharge
rate for a given load. This demonstrates the char-
Table 1. Description
Parameter
Value
Operating
Temperature
1 = 0 to 70 °C
6 = –40 to 85 °C
Storage
Temperature
–40 to 85 °C
Nominal Crystal
Frequency
32.768 kHz
Load Capacitance
12.5 pF
Nominal
Battery Voltage
2.8 V
Nominal
Battery Capacity
48 mAh
120 mAh
Battery Chemistry
Li(CF)x
M4T28
M4T32
acteristically flat voltage level supplied by the battery until very near the end of its life. These
discharge levels have been greatly accelerated 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)
5
Average Insertion Force
Average Extraction Force
12.5
10
7.5
5
2.5
0
1
2
3
4
5
6
7
8
9
10
Number of Extractions
AI02526
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M4TXX-BR12SH
Figure 3. Battery Discharge Rates
LOAD CHARACTERISTICS
3.5
Temp: 20˚C
Voltage (V)
3.0
2.5
2.0
15kΩ
30kΩ
100kΩ
1.5
1.0
0
200 400 600 800 1000 1200 1400 1600 1800 2000
Duration (hrs.)
(A)
LOAD CHARACTERISTICS
3.5
Temp: 20˚C
Voltage (V)
3.0
2.5
2.0
15kΩ
30kΩ
50kΩ
100kΩ
1.5
1.0
0
1000
2000
3000
4000
Duration (hrs.)
(B)
BATTERY LIFE
For information on Data Retention Life and Battery
Storage Life, please refer to the Application Note
AN1012.
5000
6000
AI02519
Figure 4. DIP Extractor Tool
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 sockets
do NOT wave solder SOIC.
AI02527
For battery disposal information, see on the web at
www.rayovac.com.
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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 device, please contact the STMicroelectronics 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
mm
inches
Symb
Typ
Min
A
Max
Typ
Min
Max
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
Figure 5. M4T28-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 48 mAh Battery & Crystal,
Package Outline
A1
eA
A2
A
A3
B
L
eB
D
E
SHTK-A
Drawing is not to scale.
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M4TXX-BR12SH
Table 4. M4T32-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal,
Package Mechanical Data
mm
inches
Symb
Typ
Min
A
Max
Typ
Min
Max
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
Figure 6. M4T32-BR12SH - TIMEKEEPER 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal,
Package Outline
A1
eA
A2
A
A3
B
L
eB
D
E
SHTK-A
Drawing is not to scale.
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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:
[email protected]
(for application support)
[email protected]
(for general enquiries)
Please remember to include your name, company, location, telephone number and fax number.
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted
by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject
to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not
authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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 1999 STMicroelectronics - All Rights Reserved
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