M41T56 SGS-Thomson-Microelectronics, M41T56 Datasheet
M41T56
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M41T56 Summary of contents
Page 1
... Serial Data Address Input / Output SCL Serial Clock V Battery Supply Voltage BAT V Supply Voltage CC V Ground SS March 2000 SO8 (M) 150mil Width Figure 1. Logic Diagram BAT OSCI M41T56 SCL V SS M41T56 ® SRAM SNAPHAT (SH) Battery & Crystal 1 SOH28 (MH) OSCO SDA FT/OUT AI02304B 1/19 ...
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... Typical data retention time is in excess of 10years with a 50mAh 3V lithium cell. The M41T56 is sup- plied in 8 lead Plastic SOIC package or 28 lead SNAPHAT package. The 28 pin 330mil SOIC provides sockets with ...
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... CAUTION: Negative undershoots below –0.3V are not allowed on any pin while in the Battery Back-up mode. CAUTION: Do NOT wave solder SOIC to avoid damaging SNAPHAT sockets. OPERATION The M41T56 clock operates as a slave device on the serial bus. Access is obtained by implementing a start condition followed by the correct slave ad- dress (D0h) ...
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... M41T56 Figure 3. Block Diagram OSCI OSCILLATOR 32.768 kHz OSCO FT/OUT VOLTAGE V CC SENSE and V SS SWITCH V BAT CIRCUITRY SCL SERIAL BUS INTERFACE SDA Table 3. Register Map Address Seconds Minutes ( CEB Years 7 OUT FT Note: 1. When CEB is set to ’ ...
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... By definition, a device that gives out a message is called "transmitter", the receiving device that gets the message is called "receiver". The device that controls the message is called "master". The de- vices that are controlled by the master are called "slaves". Parameter M41T56 0.7V CC 0.3V CC AI02568 pulse per bit of data ...
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... Load Capacitance L Note: Load capacitors are integrated within the M41T56. Circuit board layout considerations for the 32.768 kHz crystal of minimum trace lengths and isolation from RF generating signals should be taken into account. STMicroelectronics recommends the KDS DT-38 Tuning Fork Type quartz crystal for industrial temperature operations. ...
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... In this case, the transmitter must leave the data line High to enable the master to generate the STOP condition. M41T56 Min Max Unit 0 ns 300 µ ...
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... Figure 9). READ MODE In this mode, the master reads the M41T56 slave after setting the slave address (see Figure 11). Following the write mode control bit (R and the acknowledge bit, the word address A ...
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... This will prevent a transition of data during the read. Note: This 250ms delay affects only the clock reg- ister update and does not alter the actual clock time. M41T56 STOP CONDITION AI00587 CLOCK PULSE FOR ACKNOWLEDGEMENT ...
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... CLOCK CALIBRATION The M41T56 is driven by a quartz controlled oscil- lator with a nominal frequency of 32,768Hz. The devices are tested not to exceed 35ppm (parts per million) oscillator frequency error at 25°C, which equates to about ±1.53 minutes per month. With the calibration bits properly set, the accuracy of each M41T56 improves to better than +1/– ...
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... BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS Figure 12. Alternate Read Mode Sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS WORD DATA n ADDRESS (n) WORD S ADDRESS (n) SLAVE ADDRESS DATA n+X P DATA n DATA n+1 M41T56 DATA n+1 DATA n+X P AI00591 DATA n DATA n+1 AI00899 DATA n+X P AI00895 11/19 ...
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... CALIBRATION NEGATIVE CALIBRATION Two methods are available for ascertaining how much calibration a given M41T56 may require. The first involves simply setting the clock, letting it run for a month and comparing known accu- rate reference (like WWV broadcasts). While that may seem crude, it allows the designer to give the ...
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... Figure 14. Crystal Accuracy Across Temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 – -0.038 ppm ( – Temperature C M41T56 AI00999 13/19 ...
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... Caution: Do not place the SNAPHAT battery package "M4Txx-BR12SHx" in conductive foam since this will drain the lithium button-cell battery. For a list of available options or for further information on any aspect of this device, please contact the STMicroelectronics Sales Office nearest to you. Table 12. Revision History Date March 1999 First Issue 12/23/99 SOH28 package added 03/21/00 Series Resistance Max Value Changed (Table 8) 14/19 M41T56 Revision Details ...
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... Min Max 1.35 1.75 0.10 0.25 0.33 0.51 0.19 0.25 4.80 5.00 3.80 4.00 – – 5.80 6.20 0.25 0.50 0.40 0.90 0° 8° inches Typ Min 0.053 0.004 0.013 0.007 0.189 0.150 0.050 – 0.228 0.010 0.016 0° 45˚ M41T56 Max 0.069 0.010 0.020 0.010 0.197 0.157 – 0.244 0.020 0.035 8° 0.004 15/19 ...
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... M41T56 Table 14. SOH28 - 28 lead Plastic Small Outline, 4-socket battery SNAPHAT, Package Mechanical Data Symb Typ 1. Figure 16. SOH28 - 28 lead Plastic Small Outline, 4-socket battery SNAPHAT, Package Outline SOH-A Drawing is not to scale. 16/19 mm Min Max 3.05 0.05 0.36 2.34 2.69 0.36 0.51 0.15 0.32 17.71 18.49 8.23 8.89 – ...
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... Figure 17 4-pin SNAPHAT Housing for 48 mAh Battery & Crystal, Package Outline Drawing is not to scale. mm Min Max 9.78 6.73 7.24 6.48 6.99 0.38 0.46 0.56 21.21 21.84 14.22 14.99 3.20 3.61 2.03 2. M41T56 inches Typ Min Max 0.385 0.265 0.285 0.255 0.275 0.015 0.018 0.022 0.835 0.860 0.560 0.590 0.126 0.142 0.080 0.090 SHTK-A ...
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... M41T56 Table 16 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal, Package Mechanical Data Symb Typ Figure 18 4-pin SNAPHAT Housing for 120 mAh Battery & Crystal, Package Outline Drawing is not to scale. 18/19 mm Min Max 10.54 8.00 8.51 7.24 8.00 0.38 0.46 0.56 21.21 21.84 17.27 18.03 3.20 3.61 2.03 2. ...
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... Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. The ST logo is registered trademark of STMicroelectronics 2000 STMicroelectronics - All Rights Reserved All other names are the property of their respective owners. STMicroelectronics GROUP OF COMPANIES http://www.st.com M41T56 19/19 ...