ADM697

Superior Upgrade for MAX696/MAX697
Specified Over Temperature
Adjustable Low Line Voltage Monitor
Power OK/Reset Time Delay
Reset Assertion Down to 1 V V_CC
Watchdog Timer-100 ms, 1.6 s, or Adjustable
Low Switch On Resistance
1.5 Normal, 20 in Backup
600 nA Standby Current
Automatic Battery Backup Switching (ADM696)
Fast On-Board Gating of Chip Enable Signals (ADM697)
Voltage Monitor for Power Fail or Low Battery Warning

The ADM696/ADM697 supervisory circuits offer complete single chip solutions for power supply monitoring and battery control functions in microprocessor systems. These functions include mP reset, backup-battery switchover, watchdog timer, CMOS RAM write protection, and power failure warning.

The ADM696/ADM697 are available in 16-pin DIP and small outline packages and provide the following functions:
1. Power-On Reset output during power-up, power-down and brownout conditions. The RESET voltage threshold is adjustable using an external voltage divider. The RESET output remains operational with VCC as low as 1 V.
2. A Reset pulse if the optional watchdog timer has not been toggled within specified time.
3. Separate watchdog time-out and low line status outputs.
4. Adjustable reset and watchdog timeout periods.
5. A 1.3 V threshold detector for power fail warning, low battery detection, or to monitor a power supply other than VCC.
6. Battery backup switching for CMOS RAM, CMOS microprocessor or other low power logic (ADM696).
7. Write protection of CMOS RAM or EEPROM (ADM697).

The ADM696/ADM697 is fabricated using an advanced epitaxial CMOS process combining low power consumption (5 mW), extremely fast Chip Enable gating (5 ns) and high reliability. RESET assertion is guaranteed with VCC as low as 1 V. In addition, the power switching circuitry is designed for minimal voltage drop thereby permitting increased output current drive of up to 100 mA without the need for an external pass transistor.