M41T80M6E STMicroelectronics, M41T80M6E Datasheet
M41T80M6E
Specifications of M41T80M6E
M41T80M6
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M41T80M6E Summary of contents
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Features ■ Counters for tenths/hundredths of seconds, seconds, minutes, hours, day, date, month, year, 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 ...
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Contents Contents 1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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M41T80 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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M41T80 1 Description The M41T80 is a low power serial RTC with a built-in 32.768 kHz oscillator (external crystal controlled). Eight registers (see clock/calendar function and are configured in binary coded decimal (BCD) format. An additional 12 registers provide status/control ...
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Description Figure 2. 8-pin SOIC connections 1. Open drain output Figure 3. Block diagram CRYSTAL SDA SCL 1. Open drain output 6/ M41T80 F 32K ( REAL TIME ...
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M41T80 2 Operation The M41T80 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 20 bytes contained in the device can then be ...
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Operation 2.1.4 Data valid The state of the data line represents valid data when after a start condition, the data line is stable for the duration of the high period of the clock signal. The data on the line may ...
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M41T80 Figure 5. Acknowledgement sequence START SCL FROM MASTER DATA OUTPUT BY TRANSMITTER DATA OUTPUT BY RECEIVER Figure 6. Bus timing requirements sequence SDA t BUF SCL MSB t HD:STA HIGH ...
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Operation Table 2. AC characteristics Sym 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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M41T80 Figure 7. Slave address location START Figure 8. READ mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS DATA n+X Figure 9. Alternative READ mode sequence BUS ACTIVITY: MASTER SDA LINE S BUS ACTIVITY: SLAVE ADDRESS ...
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Operation 2.3 WRITE mode In this mode the master transmitter transmits to the M41T80 slave receiver. Bus protocol is shown in Figure 10: WRITE mode sequence on page and slave address, a logic '0' (R/W=0) is placed on the bus ...
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M41T80 3 Clock operation The M41T80 is driven by a quartz-controlled oscillator with a nominal frequency of 32,768 Hz. The accuracy of the real-time clock depends on the frequency of the quartz crystal that is used as the time-base for ...
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Clock operation Table 3. Clock register map Addr D7 00h 01h ST 02h 0 03h CEB 04h 0 05h 0 06h 0 07h 08h OUT 09h 32KE 0Ah AFE SQWE 0Bh RPT4 RPT5 0Ch RPT3 0Dh RPT2 0Eh RPT1 0Fh ...
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M41T80 3.2 Setting alarm clock registers Address locations 0Ah-0Eh contain the alarm settings. The alarm can be configured to go off at a prescribed time on a specific month, date, hour, minute, or second or repeat every year, month, day, ...
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Clock operation Table 5. Square wave output frequency RS3 3.3 Full-time 32 KHz square wave output The M41T80 offers the user a special 32 ...
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M41T80 3.5 Output driver pin When the AFE bit and SQWE bit are not set, the IRQ/OUT/SQW pin becomes an output driver that reflects the contents the control register. In other words, when D7 (OUT bit) of ...
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... These are stress ratings only and operation of the device at these or any other conditions above those indicated in the operating sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Refer also to the STMicroelectronics SURE Program and other relevant quality documents. Table 7. ...
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M41T80 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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... Load capacitance L 1. Externally supplied if using the SO8 package. STMicroelectronics recommends the KDS DT-38: 1TA/1TC252E127, Tuning Fork Type (thru-hole) or the DMX-26S: 1TJS125FH2A212, (SMD) quartz crystal for industrial temperature operations. 2. Load capacitors are integrated within the M41T80. Circuit board layout considerations for the 32.768 kHz crystal of minimum trace lengths and isolation from RF generating signals should be taken into account ...
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M41T80 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 at: www.st.com. ...
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Package mechanical data Figure 13. SO8 – 8 lead plastic small outline, 150 mils body width, package mechanical drawing Drawing is not to scale. Table 12. SO8 – 8 lead plastic small outline, 150 mils body width, ...
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M41T80 7 Part numbering Table 13. Ordering information scheme Example: Device type M41T Supply voltage and write protect voltage 2 Package M = SO8 Temperature range 6 = –40 ° ...
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Revision history 8 Revision history Table 14. Revision history Date Revision Oct-2002 15-Jun-04 29-Aug-2006 15-Apr-2010 24/25 1 First issue Reformatted; add lead-free information; update characteristics 2 (Table 7, Table 10, Table 13) Changed document to new template; added new features ...
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... M41T80 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. ...