M41T11_08 STMICROELECTRONICS [STMicroelectronics], M41T11_08 Datasheet
M41T11_08
Related parts for M41T11_08
M41T11_08 Summary of contents
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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 resistance operation 2 ■ Serial interface supports I protocol) ...
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Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Description The M41T11is a low-power serial real time clock 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 are configured ...
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Table 1. Signal names OSCI OCSO FT/OUT SDA SCL V BAT Figure 2. 8-pin SOIC connections Figure 3. 28-pin SOIC connections 6/29 Oscillator input Oscillator output Frequency test/output driver (open drain) Serial data address input/output Serial ...
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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 SECONDS MINUTES DIVIDER CENTURY/HOURS MONTH CONTROL LOGIC CONTROL ( ADDRESS ...
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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 accessed ...
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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 after ...
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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 tHD:STA ...
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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 HD:STA ...
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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 12/29 ...
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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 bus ...
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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 2 (hours ...
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Table 3. Register map Address (2) 2 CEB OUT 1. Keys SIGN bit FT = FREQUENCY TEST bit ST = STOP bit OUT = Output ...
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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 corresponds to ...
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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 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 conditions above ...
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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 under ...
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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 at 5V; sampled only, not 100% tested. ...
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Figure 15. Power down/up mode AC waveforms tPD SDA SCL Table 9. Power down/up AC characteristics Symbol Parameter t SCL and SDA SCL and SDA at V REC IH 1. Valid ...
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Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a Lead-free second level interconnect. The category of second Level Interconnect is marked on the package and on the inner ...
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Figure 16. SO8 – 8-lead plastic small outline package outline Drawing is not to scale. Table 11. SO8 – 8-lead plastic small outline (150 mils body width) pack. mech. data millimeters Symbol ...
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Figure 17. SOH28 – 28-lead plastic small outline, battery snaphat package outline B 1. Drawing is not to scale. Table 12. SOH28 – 28-lead plastic small outline, battery snaphat pack. mech. data Symb Typ ...
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Figure 18. SH – 4-pin SNAPHAT housing for 48mAh battery & crystal package outline 1. Drawing is not to scale. Table 13. SH – 4-pin SNAPHAT housing for 48 mAh battery & crystal, package mechanical data mm Symb Typ Min ...
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Figure 19. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package outline 1. Drawing is not to scale. Table 14. SH – 4-pin SNAPHAT housing for 120mAh battery & crystal, package mech. data Symb Typ ...
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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 to ...
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Revision history Table 17. Revision history Date Revision Mar-1999 1.0 23-Dec-1999 1.1 25-Jul-2000 1.2 12-Dec-2000 1.3 24-Jan-2001 2.0 27-Feb-2001 3.0 17-Jul-2001 3.1 27-Nov-2001 3.2 21-Jan-2002 3.3 01-May-2002 3.4 03-Jul-2002 3.5 07-Nov-2002 3.6 15-Jun-2004 4.0 14-Dec-2004 5.0 22-Aug-2006 03-Oct-2007 02-May-2008 ...
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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 ...