M4T32-BR12SH1 STMicroelectronics, M4T32-BR12SH1 Datasheet
M4T32-BR12SH1
Specifications of M4T32-BR12SH1
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M4T32-BR12SH1 Summary of contents
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V, 256 Kbit (32 Kbit x 8) TIMEKEEPER Features ■ Integrated, ultra low power SRAM, real-time clock, power-fail control circuit and battery ™ ■ BYTEWIDE RAM-like clock access ■ BCD coded year, month, day, date, hours, minutes, and seconds ...
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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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M48T35AV List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of figures List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... The SOIC and battery/crystal packages are shipped separately in plastic anti-static tubes or in tape & reel form. For the 28-lead SOIC, the battery/crystal package part numbers are M4T28-BR12SH1 (48 mAh lithium battery SNAPHAT), M4T32-BR12SH1 (120 mAh lithium battery SNAPHAT), and M4T32-BR12SH6 (120 mAh lithium battery SNAPHAT, –40 to +85 °C crystal). Figure 1. ...
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Description Table 1. Signal names A0-A14 DQ0-DQ7 Figure 2. DIP connections Figure 3. SOIC connections 6/29 Address inputs Data inputs / outputs Chip enable Output enable WRITE enable Supply voltage Ground A14 1 ...
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M48T35AV Figure 4. Block diagram 32,768 Hz CRYSTAL LITHIUM CELL OSCILLATOR AND CLOCK CHAIN POWER VOLTAGE SENSE V PFD AND SWITCHING CIRCUITRY V CC Doc ID 6845 Rev 8 Description BiPORT SRAM ARRAY A0-A14 DQ0-DQ7 32,760 x ...
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Operation modes 2 Operation modes As Figure 4 on page 7 oscillator of the M48T35AV are integrated on one silicon chip. The two circuits are interconnected at the upper eight memory locations to provide user accessible BYTEWIDE™ clock information in ...
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M48T35AV The state of the eight three-state data I/O signals is controlled by E and G. If the outputs are activated before t the Address Inputs are changed while E and G remain active, output data will remain valid for ...
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Operation modes 2.2 WRITE mode The M48T35AV is in the WRITE mode whenever W and E are low. The start of a WRITE is referenced from the latter occurring falling edge WRITE is terminated by ...
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M48T35AV Table 4. WRITE mode AC characteristics Symbol t AVAV t AVWL t AVEL t WLWH t ELEH t WHAX t EHAX t DVWH t DVEH t WHDX t EHDX (2)(3) t WLQZ t AVWH t AVEH (2)(3) t WHQX ...
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Operation modes Also rises, the battery voltage is checked. If the voltage is less than approximately CC 2 internal battery not OK (BOK) flag will be set. The BOK flag can be checked after power up. ...
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... The STOP bit is the MSB of the seconds register. Setting '1' stops the oscillator. The M48T35AV is shipped from STMicroelectronics with the STOP bit set to a '1.' When reset to a '0,' the M48T35AV oscillator starts within 1 second. ...
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Clock operations Table 5. Register map Address D7 7FFFh 7FFEh 0 7FFDh 0 7FFCh 0 7FFBh 0 7FFAh 0 7FF9h ST 7FF8h W Keys SIGN bit FT = FREQUENCY TEST bit (must be set to '0' upon power ...
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M48T35AV occurs within a 64 minute cycle. The first 62 minutes in the cycle may, once per minute, have one second either shortened by 128 or lengthened by 256 oscillator cycles binary '1' is loaded into the register, ...
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Clock operations Figure 9. Crystal accuracy across temperature ppm 20 0 -20 -40 -60 -80 -100 0 Figure 10. Clock calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 16/29 ΔF = -0.038 ppm 2 ± 10 ...
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M48T35AV 3.6 V noise and negative going transients CC I transients, including those produced by output switching, can produce voltage CC fluctuations, resulting in spikes on the V capacitors are used to store energy which stabilizes the V bypass capacitors ...
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Maximum ratings 4 Maximum ratings Stressing the device above the rating listed in the absolute maximum ratings table may cause permanent damage to the device. These are stress ratings only and operation of the device at these or any other ...
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M48T35AV 5 DC and AC parameters This section summarizes the operating and measurement conditions, as well as the DC and AC characteristics of the device. The parameters in the following DC and AC characteristic tables are derived from tests performed ...
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DC and AC parameters Table 9. DC characteristics Symbol Parameter I Input leakage current LI (2) I Output leakage current LO I Supply current CC I Supply current (standby) TTL CC1 I Supply current (standby) CMOS CC2 (3) V Input ...
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... V Battery backup switchover voltage SO (3) t Expected data retention time DR 1. Valid for ambient operating temperature: T noted). 2. All voltages referenced ° CAPHAT™ and M4T32-BR12SH1 SNAPHAT (1) Parameter (min) V fall time CC fall time CC (max) V rise time CC rise time °C or – ° may result in deselection/write protection not occurring until 200 µs after F may cause corruption of RAM data ...
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Package mechanical data 6 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available ...
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M48T35AV Figure 15. SOH28 – 28-lead plastic small outline, 4-socket battery SNAPHAT package outline B Note: Drawing is not to scale. Table 13. SOH28 – 28-lead plastic small outline, 4-socket battery SNAPHAT mech. data Symb ...
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Package mechanical data Figure 16. SH – 4-pin SNAPHAT Note: Drawing is not to scale. Table 14. SH – 4-pin SNAPHAT data Symb 24/29 ® housing for 48 mAh battery ...
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M48T35AV Figure 17. SH – 4-pin SNAPHAT Note: Drawing is not to scale. Table 15. SH – 4-pin SNAPHAT data Symb ® housing for 120 mAh battery & crystal, pack. ...
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... Do not place the SNAPHAT will drain the lithium button-cell battery. For other options, or for more information on any aspect of this device, please contact the ST sales office nearest you. Table 17. SNAPHAT Part number M4T28-BR12SH1 M4T32-BR12SH1 M4T32-BR12SH6 26/29 M48T 35AV = 2.7 to 3.0 V PFD ® ...
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M48T35AV 8 Environmental information Figure 18. Recycling symbols This product contains a non-rechargeable lithium (lithium carbon monofluoride chemistry) button cell battery fully encapsulated in the final product. Recycle or dispose of batteries in accordance with the battery manufacturer's instructions and ...
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Revision history 9 Revision history Table 18. Document revision history Date Revision Nov-1999 21-Apr-2000 29-May-2000 20-Jul-2001 20-May-2002 31-Mar-2003 01-Apr-2004 21-Nov-2007 23-Mar-2009 21-Oct-2010 28/29 1 First issue 2 From preliminary data to datasheet 2.1 t change (Table 10) FB Reformatted; temp./voltage ...
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... M48T35AV Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...