M41T11_11 STMICROELECTRONICS [STMicroelectronics], M41T11_11 Datasheet
M41T11_11
Related parts for M41T11_11
M41T11_11 Summary of contents
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Serial real-time clock (RTC) with 56 bytes of NVRAM Features ■ Counters for seconds, minutes, hours, day, date, month, years and century ■ 32 KHz crystal oscillator integrating load capacitance (12.5 pF) providing exceptional oscillator stability and high crystal series ...
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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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M41T11 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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M41T11 1 Description The M41T11 is a low-power serial real-time clock (RTC) with 56 bytes of NVRAM. A built-in 32.768 kHz oscillator (external crystal controlled) and the first 8 bytes of the RAM are used for the clock/calendar function and ...
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Description Table 1. Signal names OSCI OCSO FT/OUT SDA SCL V BAT Figure 2. 8-pin SOIC connections Figure 3. 28-pin SOIC connections 6/30 Oscillator input Oscillator output Frequency test/output driver (open drain) Serial data address input/output ...
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M41T11 Figure 4. 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 1 Hz DIVIDER CONTROL LOGIC ADDRESS REGISTER Doc ID 6103 Rev 10 Description ...
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Operation 2 Operation The M41T11 clock operates as a slave device on the serial bus. Access is obtained by implementing a start condition followed by the correct slave address (D0h). The 64 bytes contained in the device can then be ...
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M41T11 2.1.3 Stop data transfer A change in the state of the data line, from low to high, while the clock is high, defines the STOP condition. 2.1.4 Data valid The state of the data line represents valid data when ...
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Operation Figure 6. Acknowledgement sequence START SCLK FROM MASTER DATA OUTPUT BY TRANSMITTER DATA OUTPUT BY RECEIVER Figure 7. Bus timing requirements sequence SDA tBUF SCL STOP and S = START 10/ MSB ...
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M41T11 Table 2. AC characteristics Symbol f SCL clock frequency SCL t Clock low period LOW t Clock high period HIGH t SDA and SCL rise time R t SDA and SCL fall time F START condition hold time t ...
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Operation Figure 8. Slave address location START Figure 9. Read mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS DATA n+X Figure 10. Alternate read mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS ...
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M41T11 2.3 Write mode In this mode the master transmitter transmits to the M41T11 slave receiver. Bus protocol is shown in Figure 11. Following the START condition and slave address, a logic '0' (R placed on the ...
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Clock operation 3 Clock operation The eight byte clock register (see and time from the clock binary coded decimal format. Seconds, minutes, and hours are contained within the first three registers. Bits D6 and D7 of clock register ...
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M41T11 Table 3. Register map Address (2) 2 CEB OUT 1. Keys SIGN bit FT = FREQUENCY TEST bit ST = STOP bit OUT = ...
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Clock operation adjustment per calibration step in the calibration register. Assuming that the oscillator is in fact running at exactly 32,768 Hz, each of the 31 increments in the calibration byte would represent +10.7 or –5.35 seconds per month which ...
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M41T11 Figure 12. Crystal accuracy across temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 –30 –20 Figure 13. Clock calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION – ...
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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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M41T11 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 6. Capacitance Symbol C Input capacitance (SCL) IN (3) C Output capacitance (SDA, FT/OUT) OUT t Low-pass filter input time constant (SDA and SCL Effective capacitance measured with power supply ...
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M41T11 Figure 15. Power down/up mode AC waveforms tPD SDA SCL Table 9. Power down/up AC characteristics Symbol t SCL and SDA SCL and SDA at V REC 1. Valid for ambient ...
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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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M41T11 Figure 16. SO8 – 8-lead plastic small outline package outline A2 1. Drawing is not to scale. Table 11. SO8 – 8-lead plastic small outline (150 mils body width) package mechanical data Symbol ccc ...
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Package mechanical data Figure 17. SOH28 – 28-lead plastic small outline, battery SNAPHAT outline 1. Drawing is not to scale. Table 12. SOH28 – 28-lead plastic small outline, battery SNAPHAT mechanical data Symb ...
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M41T11 Figure 18. SH – 4-pin SNAPHAT outline 1. Drawing is not to scale. Table 13. SH – 4-pin SNAPHAT mechanical data Symb ® housing for 48 mAh battery & ...
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Package mechanical data Figure 19. SH – 4-pin SNAPHAT outline 1. Drawing is not to scale. Table 14. SH – 4-pin SNAPHAT mech. data Symb 26/30 ® housing for 120 ...
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M41T11 7 Part numbering Table 15. Ordering information scheme Example: Device type M41T Supply voltage 2 Package M = SO8 (150 mil width) ( SOH28 Temperature range 6 = –40 ...
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Environmental information 8 Environmental information Figure 20. 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 ...
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M41T11 9 Revision history Table 17. Revision history Date Revision Added lead-free second level interconnect information to cover page and 03-Oct-2007 7 Package mechanical 02-May-2008 8 Updated Updated 08-Jan-2009 9 added Added ESR footnote to Removed shipping method in tubes ...
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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 ...