m41t00cap STMicroelectronics, m41t00cap Datasheet
m41t00cap
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m41t00cap Summary of contents
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... Oscillator stop detection ■ Battery backup ■ Operating temperature 70°C ■ Self-contained battery and crystal in CAPHAT™ DIP package ■ RoHS compliant – Lead-free second level interconnect March 2009 M41T00CAP 24 1 PCDIP24(PC) Battery/crystal CAPHAT Rev 3 TM 1/27 www.st.com 1 ...
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... Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.7 READ mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.8 WRITE mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.9 Data retention mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 4 Clock operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 4.1 Clock registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.2 Calibrating the clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.3 Century bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.4 Oscillator fail detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.5 Output driver pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.6 Initial power-on default . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 7 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2/27 M41T00CAP ...
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... M41T00CAP 9 Environmental information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 10 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Contents 3/27 ...
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... Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 6. Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 7. DC characteristics Table 8. Power down/up AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Table 9. Power down/up trip points DC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Table 10. AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Table 11. PCDIP24 – 24-pin plastic DIP, battery CAPHAT™, package mechanical data . . . . . . . . . 23 Table 12. Ordering information scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Table 13. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4/27 M41T00CAP ...
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... M41T00CAP List of figures Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Figure 2. DIP connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 3. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 4. Serial bus data transfer sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 5. Acknowledgement sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 6. Slave address location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 7. READ mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 8. Alternative READ mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 9. WRITE mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Figure 10. Crystal accuracy across temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 11 ...
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... Description 1 Description The M41T00CAP is a low-power serial RTC with integral battery and crystal in ST’s 24-pin CAPHAT™ package. It includes a crystal controlled, 32.768 kHz oscillator and has a built-in power sense circuit which detects power failures and automatically switches to the backup battery when a power failure occurs. ...
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... “don’t use”. Do not connect. Must be allowed to float. Do not connect FT/OUT M41T00CAP SCL SDA AI01028 ...
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... Figure 3. Block diagram CRYSTAL SDA SCL BAT PFD 1. Open drain output 8/27 REAL TIME CLOCK CALENDAR OSCILLATOR FAIL CIRCUIT 32KHz OSCILLATOR RTC & CALIBRATION FREQUENCY TEST INTERFACE LOGIC OUTPUT WRITE PROTECT COMPARE M41T00CAP FT (1) FT/OUT OUT INTERNAL POWER AI09168 ...
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... M41T00CAP 3 Operation The M41T00CAP clock operates as a slave device on the I by implementing a start condition followed by the correct slave address (D0h). The 8 bytes contained in the device can then be accessed sequentially in the following order: 1. Seconds register 2. Minutes register 3. Century/hours register 4. Day register 5. Date register 6 ...
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... A master receiver must signal an end of data to the slave transmitter by not generating an acknowledge on the last byte that has been clocked out of the slave. In this case the transmitter must leave the data line high to enable the master to generate the STOP condition. 10/27 M41T00CAP ...
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... The address pointer is only incremented on reception of an acknowledge clock. The M41T00CAP slave transmitter will now place the data byte at address An+1 on the bus, the master receiver reads and acknowledges the new byte and the address pointer is incremented to “ ...
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... SDA LINE S BUS ACTIVITY: SLAVE ADDRESS DATA n+X Figure 8. Alternative READ mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS 12/27 Figure R/W SLAVE ADDRESS WORD S ADDRESS (An) SLAVE ADDRESS P DATA n DATA n+1 M41T00CAP 8). A AI00602 DATA n DATA n+1 AI00899 DATA n+X P AI00895 ...
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... M41T00CAP 3.8 WRITE mode In this mode the master transmitter transmits to the M41T00CAP slave receiver. Bus protocol is shown in (R/W=0) is placed on the bus and indicates to the addressed device that word address “An” will follow and written to the on-chip address pointer. The data word to be written to the memory is strobed in next and the internal address pointer is incremented to the next address location on the reception of an acknowledge clock ...
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... seconds Seconds 10 minutes Minutes 10 hours Hours (24-hour format Day of week 10 date Date: day of month 0 10M Month Year S Calibration Function/range BCD format D1 D0 Seconds Minutes Century/hours Day Date Month Year Calibration M41T00CAP 00-59 00-59 0-1/00-23 01-7 01-31 01-12 00-99 ...
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... Two methods are available for ascertaining how much calibration a given M41T00CAP may require. The first involves setting the clock, letting it run for a month and comparing known accurate reference and recording deviation over a fixed period of time ...
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... If CEB is set to a '0,' CB will not toggle. 16/27 for proper operation. A 500-10 kΩ resistor is recommended in order CC Δ – –0.036 ppm/° 25°C ± 5°C O – Temperature °C M41T00CAP ± 0.006 ppm/° AI07888 AI00594B ...
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... M41T00CAP 4.4 Oscillator fail detection If the oscillator fail bit (OF) is internally set to '1,' this indicates that the oscillator has either stopped, or was stopped for some period of time and can be used to judge the validity of the clock and date data. In the event the OF bit is found to be set to '1' at any time other than the initial power-up, the STOP bit (ST) should be written to a '1,' then immediately reset to '0 ...
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... Soldering temperature not to exceed 260°C for 10 seconds (total thermal budget not to exceed 150°C for longer than 30 seconds). Caution: Negative undershoots below –0.3 volts are not allowed on any pin while in the battery backup mode. 18/27 Parameter off, oscillator off) CC M41T00CAP Value Unit –55 to 125 °C –0 260 °C – ...
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... Designers should check that the operating Parameter ) ) 0.8V CC 0.2V CC (1) (2) Parameter Input capacitance Output capacitance Low-pass filter input time constant (SDA and SCL) DC and AC parameters Table 5: M41T00CAP 2 70°C 100 pF ≤ 0.7V CC 0.3V CC AI02568 ...
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... CC ≤ 0 3 (2) ( 70° tPD DON'T CARE (1)(2) Parameter before power down IH after power 70° M41T00CAP (1) Min Typ Max ±1 ±1 CC 300 70 –0.3 0 0.4 0.4 5.5 = 2.7 to 5.5 V (except where noted). CC tREC AI00596 Min Typ ...
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... M41T00CAP Table 9. Power down/up trip points DC characteristics Sym Parameter Power-fail deselect V PFD Hysteresis Battery backup switchover voltage V SO Hysteresis (3) t Expected data retention time DR 1. All voltages referenced Valid for ambient operating temperature 25° oscillator on. ...
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... Valid for ambient operating temperature Transmitter must internally provide a hold time to bridge the undefined region (300 ns max) of the falling edge of SCL. 22/27 (1) Parameter = 0 to 70° 2.7 to 5.5 V (except where noted M41T00CAP Min Typ Max Units 0 400 kHz 1.3 µs 600 ...
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... M41T00CAP 7 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 at: www.st.com. ® ECOPACK trademark. Figure 15. PCDIP24 – 24-pin plastic DIP, battery CAPHAT™, package outline Note: Drawing is not to scale ...
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... Part numbering 8 Part numbering Table 12. Ordering information scheme Example: Device type M41T Supply voltage and write protect voltage 00CAP = V = 2 Package PC = PCDIP24 Temperature range 1 = 0°C to 70°C Shipping method Blank = ECOPACK 24/27 M41T ® package, tubes M41T00CAP 00CAP PC 1 ...
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... M41T00CAP 9 Environmental information Figure 16. 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 local/national disposal and recycling regulations. Please refer to the following web site address for additional information regarding compliance statements and waste recycling www.st.com/rtc, then select " ...
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... Table 13. Document revision history Date 28-Jun-2006 20-Mar-2008 25-Mar-2009 26/27 Revision 1 First release 2 Document status upgraded to full datasheet; updated title and cover page, Section Added Section 9: Environmental Section 7: Package mechanical M41T00CAP Changes Figure Table 10. information; updated text in data. ...
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... M41T00CAP 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. ...