M41T56_11 STMICROELECTRONICS [STMicroelectronics], M41T56_11 Datasheet
M41T56_11
Related parts for M41T56_11
M41T56_11 Summary of contents
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Serial real-time clock (RTC) with 56 bytes 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 resistance ...
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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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M41T56 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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M41T56 1 Description The M41T56 is a low-power, serial real-time clock (RTC) with 56 bytes of NVRAM. A built-in 32,768 Hz 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. M41T56 block diagram OSCI OSCO FT/OUT BAT SCL SDA 6/27 Oscillator input ...
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M41T56 2 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 address (D0h). The 64 bytes contained in the device can then be ...
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Operation 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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M41T56 Figure 5. Acknowledge sequence SCLK FROM MASTER DATA OUTPUT BY TRANSMITTER DATA OUTPUT BY RECEIVER Figure 6. Bus timing requirements sequence SDA tBUF SCL P START 1 2 MSB tHD:STA tR tF tHIGH S tLOW tHD:DAT Doc ID 6104 ...
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Operation 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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M41T56 Figure 7. Slave address location Figure 8. Read mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: Figure 9. Alternative read mode sequence BUS ACTIVITY: MASTER SDA LINE BUS ACTIVITY: START SLAVE ADDRESS WORD ...
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Operation 2.3 Write mode In this mode the master transmitter transmits to the M41T56 slave receiver. Bus protocol is shown in Figure 10 on page (R placed on the bus and indicates to the addressed device that ...
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M41T56 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 2 ...
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Clock operation 3.1 Clock calibration The M41T56 is driven by a quartz-controlled oscillator with a nominal frequency of 32,768 Hz. The devices are tested not to exceed 35 ppm (parts per million) oscillator frequency error at 25 °C, which equates ...
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M41T56 Figure 11. Crystal accuracy across temperature Frequency (ppm –20 –40 –60 –80 –100 –120 –140 –160 –40 Figure 12. Clock calibration NORMAL POSITIVE CALIBRATION NEGATIVE CALIBRATION 3.2 Output driver pin When the FT bit is not set, ...
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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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M41T56 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 characteristics tables are derived from tests performed ...
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DC and AC parameters Table 7. DC characteristics Symbol Parameter I Input leakage current LI I Output leakage current LO I Supply current CC1 I Supply current (standby) CC2 V Input low voltage IL V Input high voltage IH V ...
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M41T56 Table 9. Power down/up mode AC characteristics Symbol t SCL and SDA (min PFD 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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M41T56 Figure 15. SO8 – 8-pin plastic small package outline A2 1. Drawing is not to scale. Table 11. SO8 – 8-pin plastic small outline, package mechanical data Symbol ccc ...
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Package mechanical data Figure 16. Carrier tape for SO8 package (150-mil body width) T TOP COVER TAPE K 0 Table 12. Carrier tape dimensions for SO8 package (150-mil body width) Package 1.50 12.00 1.75 SO8 +0.10/ ±0.30 ...
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M41T56 Figure 17. Reel schematic D A Full radius Table 13. Reel dimensions for 12 mm carrier tape - SO8 package (150-mil body width (max) (min) 330 mm 1.5 mm (13-inch) Note: The dimensions given in parameters. 40mm ...
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Part numbering 7 Part numbering Table 14. Ordering information scheme Example: Device type M41T Supply voltage and write protect voltage 4 Package M = SO8 Temperature range 6 = –40 °C to ...
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M41T56 8 References ● The crystal component supplier KDS as cited in characteristics on page 18 Table 8: Crystal electrical can be contacted at http://www.kds.info/index_en.htm Doc ID 6104 Rev 9 References 25/27 ...
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Revision history 9 Revision history Table 15. Document revision history Date Revision Mar-1999 1.0 First issue 23-Dec-1999 1.1 SOH28 package added 21-Mar-2000 1.2 Series resistance max value changed 30-Nov-2000 1.3 Added PSDIP8 package 25-Jan-2001 1.4 Corrected graphic, measurements of PSDIP8 ...
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M41T56 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 ...