Product Summary

The BQ4822YMA-70 RTC Module is a nonvolatile 65,536-bit SRAM organizedas 8192 words by 8 bits with an integral real- time clock and CPU supervisor. The CPU supervisor provides a programmable watchdog timer and a microprocessor reset. Other features include an alarm, power-fail and periodic interrupt, and a battery low warning. The BQ4822YMA-70 combines an internal lithium battery, quartz crystal, clock and power-fail chip, and a full CMOS SRAM in a plastic 28-pin DIP module. The RTC Module BQ4822YMA-70 directly replaces industry-standard SRAMs and also fits into many EPROM and EEPROM sockets without any requirement for special write timing or limitations on the number of write cycles.

Parametrics

BQ4822YMA-70 absolute maximum ratings: (1)VCC, DC voltage applied on VCC relative to VSS: -0.3 to 7.0 V; (2)VT, DC voltage applied on any pin excluding VCC; (3)relative to VSS: -0.3 to 7.0 V when VT≦VCC + 0.3; (4)TOPR, Operating temperature: 0 to +70 ℃; (5)TSTG, Storage temperature (VCC off; oscillator off): -40 to +70 ℃; (6)TBIAS, Temperature under bias: -10 to +70 ℃; (7)TSOLDER, Soldering temperature: +260 ℃ For 10 seconds.

Features

BQ4822YMA-70 features: (1)Integrated SRAM, real-time clock, CPU supervisor, crystal, power-fail circuit, and battery; (2)Real-Time Clock counts hundredths of seconds through years in BCD format; (3)RAM-like clock access; (4)Compatible with industrystandard 8K x 8 SRAMs; (5)Unlimited write cycles; (6)10-year minimum data retention and clock operation in the absence of power; (7)Automatic power-fail chip deselect and write-protection; (8)Watchdog timer, power-on reset, alarm/periodic interrupt, powerfail and battery-low warning; (9)Automatic leap year adjustment; (10)Software clock calibration for greater than ±1 minute per month accuracy.

Diagrams

BQ4822YMA-70 circuit diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)
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BQ4822YMA-70
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Data Sheet

0-1: $19.88
1-25: $19.33
25-100: $18.77
100-250: $18.24
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