X40421 Overview
The X40420/21 bines power-on reset control, watchdog timer, supply voltage supervision, and secondary supervision, manual reset, and Block Lock™ protect serial EEPROM in one package. This bination lowers system cost, reduces board space requirements, and increases reliability. Applying voltage to VCC activates the power-on reset circuit which holds RESET/RESET active for a period of time.
X40421 Key Features
- Battery Switch Backup
- VOUT: 5mA to 50mA from VCC; or 250µA from VBATT
- Fault detection register
- Selectable power-on reset timeout (0.05s, 0.2s, 0.4s, 0.8s)
- Selectable watchdog timer interval (25ms, 200ms, 1.4s, off)
- Debounced manual reset input
- Low power CMOS -25µA typical standby current, watchdog on -6µA typical standby current, watchdog off -1µA typical batter
- 4Kbits of EEPROM -16 byte page write mode -Self-timed write cycle -5ms write cycle time (typical)
- Built-in inadvertent write protection -Power-up/power-down protection circuitry -Block lock protect 0 or 1/2, of EEPROM
- 400kHz 2-wire interface
