DESCRIPTION
   The X40430/31 combines power-on reset control, watchdog timer, supply voltage supervision, secondary and third voltage supervision, manual reset, and Block Lock™ protect serial EEPROM in one package. This combination lowers system cost, reduces board space requirements, and increases reliability.

FEATURES
• Triple voltage detection and reset assertion
   —Three standard reset threshold settings
      (4.6V/2.9V/1.7V, 4.4V/2.6V/1.7V,
      2.9V/1.7V/2.4V)
   —Adjust low voltage reset threshold voltages
      using special programming sequence
   —Reset signal valid to VCC = 1V
   —Monitor three voltages or detect power fail
• Fault detection register
• Selectable power on reset timeout
• Selectable watchdog timer interval
• Debounced manual reset input
• Low power CMOS
   —30µA typical standby current, watchdog on
   —10µA typical standby current, watchdog off
• 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, 1/4, 1/2, all of EEPROM
• 400kHz I2C interface
• 2.4V to 5.5V power supply operation
• Available packages
   —14-lead SOIC, TSSOP