Maxim Integrated DS1321
The DS1321 Flexible Nonvolatile Controller with Lithium Battery Monitor is a CMOS circuit which solves the application problem of converting CMOS SRAMs into nonvolatile memory. When such a condition is detected, chip enable outputs are inhibited to accomplish write protection and the battery is switched on to supply the SRAMs with uninterrupted power. In addition to battery-backup support, the DS1321 performs the important function of monitoring the remaining capacity of the lithium battery and providing a warning before the battery reaches end-of-life.| Part No. | DS1321 |
|---|---|
| Datasheet | DS1321 Download |
| Manufacturer |  Maxim Integrated |
| Description | Flexible Nonvolatile Controller |
| Buy | Stock & Price |
FEATURES
● Converts CMOS SRAM into nonvolatile memory● Unconditionally write-protects SRAM when VCC is out of tolerance
● Automatically switches to battery backup supply when VCC power failure occurs
● Flexible memory organization - Mode 0: 4 banks with 1 SRAM each - Mode 1: 2 banks with 2 SRAMs each - Mode 2: 1 bank with 4 SRAMs each
● Monitors voltage of a lithium cell and provides advanced warning of impending battery failure
● Signals low-battery condition on active low Battery Warning output signal
● Resets processor when power failure occurs and holds processor in reset during system power-up
● Optional 5% or 10% power-fail detection
● 16-pin PDIP, 16-pin SO and 20-pin TSSOP packages
● Industrial temperature range of -40°C to +85°C PIN ASSIGNMENT VCCO VBAT TOL CEI1 CEI2 A/CEI3 B/CEI4 GND 1 2 3 4 5 6 7 8 16 VCCI 15 RST 14 BW 13 CEO1 12 CEO2 11 CEO3 10 CEO4 9 MODE DS1321 16-Pin PDIP (300 mils) VCCO VBAT TOL CEI1 CEI2 A/CEI3 B/CEI4 GND 1 2 3 4 5 6 7 8 16 VCCI 15 RST 14 BW 13 CEO1 1...
