CAT1320 and CAT1321 are complete memory and supervisory solutions for microcontroller-based systems. A 32kbit serial EEPROM memory and a system power supervisor with brown-out protection are integrated together in low power CMOS technology. Memory interface is via a 400kHz I2C bus. The CAT1320 provides a precision VCC sense circuit and drives an open drain output, RESET low whenever VCC falls below the reset threshold voltage. The CAT1321 provides a precision VCC sense circuit that drives an open drain output, RESET high whenever VCC falls below the reset threshold voltage. The power supply monitor and reset circuit protect memory and system controllers during power up/down and against brownout conditions. Five reset threshold voltages support 5V, 3.3V and 3V systems.
The CAT1320 and CAT1321 devices provide a complete memory and supervisory solution for microcontroller‑based systems. Each part combines a 32‑kbit serial EEPROM with a power‑monitoring circuit that offers active‑low (CAT1320) or active‑high (CAT1321) reset outputs, supporting 5 V, 3.3 V and 3 V systems.
The devices operate over an industrial temperature range (‑40 °C to 85 °C) and are available in 8‑pin DIP, SOIC, TSSOP and TDFN packages. They feature a 400 kHz I²C bus interface, 64‑byte page write buffer, up to 1 000 000 program/erase cycles, and 100‑year data retention. Reset thresholds are selectable to match system voltage levels, and the RESET pin can also serve as a manual reset input.
| Supported supply voltages | 5 V, 3.3 V, 3 V |
|---|---|
| I2C bus speed | 400 kHz |
| Program/Erase cycles | 1,000,000 cycles |
| Data retention | 100 years |
| Operating temperature range | -40 °C to 85 °C |
| Package types | 8‑pin DIP, SOIC, TSSOP, TDFN |
| Page write buffer size | 64 bytes |
The CAT1320 provides an active‑low reset output that goes low whenever VCC falls below the configured threshold voltage.
Both devices are rated for up to 1 000 000 program/erase cycles.
The devices support a 400 kHz I²C bus.
They are specified for industrial temperatures from –40 °C to +85 °C.