M48T37Y, M48T37V is an integrated ultra low power SRAM, real-time clock, power-fail control circuit, and battery product produced by ST company. It has frequency test output, automatic power-fail chip deselect and WRITE protection, watchdog timer and other functions.
The M48T37Y/V TIMEKEEPER SRAM is a 32 Kb x 8 non-volatile static RAM and real-time clock integrated on a single silicon chip. It features an ultra-low power design with a real-time SNAPHAT clock, power-fail control circuit, and battery backup capability. The device includes a watchdog timer, programmable alarm output, and automatic power-fail chip deselect with write protection.
| Memory Capacity | 256 Kbit (32 Kbit x 8) |
|---|---|
| Supply Voltage | 5.0 or 3.3 V |
| Package Type | 44-lead SOIC |
| Operating Temperature | -40 to +85 degrees Celsius |
The watchdog timer redirects an out-of-control microprocessor and provides a reset or interrupt to it.
When Vcc falls below the battery backup switchover voltage, the circuit connects the battery to maintain data and clock operation.