m41t80 STMicroelectronics, m41t80 Datasheet
m41t80
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m41t80 Summary of contents
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... Programmable (1Hz to 32KHz) square wave Alarm and Interrupt function Programmable Low operating current of 200µA Operating temperature of –40 to 85°C ECOPACK® package available August 2006 Serial access Real Time Clock with alarm C bus (400kHz) Rev 3 M41T80 8 1 SO8 (M) 8-pin SOIC 1/25 www.st.com 1 ...
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... Full-time 32kHz square wave output . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 3.4 Century bit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 3.5 Output driver pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.6 Preferred power-on default . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4 Maximum rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6 Package mechanical information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 7 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 8 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2/25 Bus not busy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Start data transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Stop data transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Data valid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 M41T80 ...
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... M41T80 List of tables Table 1. Signal names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Table 2. AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Table 3. Clock register map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Table 4. Alarm repeat modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Table 5. Square wave output frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Table 6. Preferred power-on default values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Table 7. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Table 8. Operating and AC measurement conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 9. Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Table 10. DC characteristics Table 11 ...
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... Figure 7. Slave address location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 8. READ mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 9. Alternative READ mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 10. WRITE mode sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Figure 11. Alarm interrupt reset waveform Figure 12. AC measurement I/O waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 13. SO8 – 8 lead plastic small outline, 150 mils body width, package mechanical drawing 4/25 M41T80 ...
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... M41T80 1 Summary description The M41T80 is a low power Serial RTC with a built-in 32.768kHz 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 of Alarm, 32kHz output, and Square Wave functions. Addresses and data are transferred serially via a two line, bi-directional I interface ...
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... Figure 3. Block diagram CRYSTAL SDA SCL 1. Open drain output 6/ IRQ/OUT/SQW ( M41T80 F 32k ( SCL 4 5 SDA V SS REAL TIME CLOCK CALENDAR 32KHz RTC W/ALARM OSCILLATOR SQUARE WAVE INTERFACE M41T80 AI07006 AF IRQ/OUT/SQW (1) F 32k (1) AI07007 ...
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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 accessed sequentially in the following order Byte: tenths/hundredths of a second register ...
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... In this case the transmitter must leave the data line High to enable the master to generate the STOP condition. Figure 4. Serial bus data transfer sequence CLOCK DATA START CONDITION 8/25 DATA LINE STABLE DATA VALID CHANGE OF DATA ALLOWED M41T80 STOP CONDITION AI00587 ...
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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 tBUF SCL MSB tHD:STA tR tF tHIGH tSU:DAT tLOW tHD:DAT Operation CLOCK PULSE FOR ACKNOWLEDGEMENT 8 9 LSB AI00601 tHD:STA tSU:STA ...
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... Note: This is true both in READ Mode and WRITE Mode. An alternate READ Mode may also be implemented whereby the master reads the M41T80 slave without first writing to the (volatile) address pointer. The first address that is read is the last one stored in the pointer (see ...
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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 R/W SLAVE ADDRESS WORD S ADDRESS (An) ...
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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 and indicates to the addressed device that word address “An” will follow and written to the on-chip address pointer. ...
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... This will prevent a transition of data during the READ. 3.1 Clock registers The M41T80 offers 20 internal registers which contain Clock, Alarm, 32kHz, Flag, Square Wave, and Control data. These registers are memory locations which contain external (user accessible) and internal copies of the data (usually referred to as BiPORT external copies are independent of internal functions except that they are updated periodically by the simultaneous transfer of the incremented internal copy ...
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... Minutes Minutes Century/ hours Day of week Day Date Month Month Year Year Control 32kHz Alarm month Al month Alarm date Al date Alarm hour Al hour Alarm minutes Al min Al sec Flags Reserved Reserved Reserved SQW M41T80 format 00-99 00-59 00-59 0-1/00-23 01-7 01-31 01-12 00-99 01-12 01-31 00-23 00-59 00-59 ...
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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, hour, minute, or second. Bits RPT5-RPT1 put the alarm in the repeat mode of operation. ...
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... Full-time 32kHz square wave output The M41T80 offers the user a special 32kHz square wave function which defaults to output on the F pin (Pin 3) as long as V 32k function is available within four seconds of initial power-up and can only be disabled by setting the 32kE Bit to '0' or the ST Bit to '1.' If not used, the F and allowed to float ...
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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 address location 08h is a '0,' then the IRQ/OUT/SQW pin will be driven low. ...
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... For SO package, Lead-free (Pb-free) lead finish: Reflow at peak temperature of 260°C (total thermal budget not to exceed 245°C for greater than 30 seconds). 18/25 Parameter off, oscillator off) CC M41T80 Value Unit –55 to 125 °C –0 260 ° ...
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... Low-pass filter input time constant (SDA and SCL Effective capacitance measured with power supply at 5V; sampled only, not 100% tested 25° 1MHz. 3. Outputs deselected. Parameter ) ) 0.8V CC 0.2V CC (1) (2) Parameter DC and AC parameters (1) M41T80 2.0 to 5.5V –40 to 85°C 100pF 50ns 0. 0. 0.7V CC 0.3V CC AI02568 Min ...
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... Fork Type (thru-hole) or the DMX-26S: 1TJS125FH2A212, (SMD) quartz crystal for industrial temperature operations. KDS can be contacted at kouhou@kdsj.co.jp or http://www.kdsj.co.jp for further information on this crystal type. 2. Load capacitors are integrated within the M41T80. Circuit board layout considerations for the 32.768kHz crystal of minimum trace lengths and isolation from RF generating signals should be taken into account. ...
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... M41T80 6 Package mechanical information 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 box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ...
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... GAUGE PLANE SO-A inches Typ Min 0.004 0.049 0.011 0.007 0.193 0.189 0.236 0.228 0.154 0.150 0.050 – 0.010 0° 0.016 0.041 M41T80 Max 0.069 0.010 0.019 0.009 0.004 0.197 0.244 0.157 – 0.020 8° 0.050 ...
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... M41T80 7 Part numbering Table 13. Ordering information scheme Example: Device type M41T Supply voltage and write protect voltage 2.0 to 5.5V CC Package M = SO8 Temperature range 6 = –40°C to 85°C Shipping method ® ECOPACK package, standard package ® ECOPACK package, tape & reel 24mm packing For other options, or for more information on any aspect of this device, please contact the ST Sales Office nearest you ...
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... First issue Reformatted; add Lead-free information; update characteristics 2.0 (Table 7, Table 10, Table Changed document to new template; added new features in summary on page 1; updated Package mechanical data in 3 Section 6: Package mechanical entire document, ecopack compliant Revision details 13) information; small text changes for M41T80 Feature ...
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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. ...