ASM802M

ASM690A/692A, ASM802L/802M, ASM805L mP Power Supply Supervisor with Battery Backup Switch Description The ASM690A / ASM692A / ASM802L / ASM802M / ASM805L offers complete single chip solutions for power supply monitoring and control battery functions in microprocessor systems. Each device implements four functions: Reset control, watchdog monitoring, battery−backup switching and power failure monitoring. In addition to microprocessor reset under power−up and power−down conditions, these devices provide battery−backup switching to maintain control in power loss and brown−out situations. Additional monitoring capabilities can provide an early warning of unregulated power supply loss before the voltage regulator drops out. The important features of these four functions are: 1.6 second watchdog timer to keep microprocessor responsive 4.40 V or 4.65 V VCC threshold for microprocessor reset at power−up and power−down SPDT (Single−pole, Double−throw) PMOS switch connects backup power to RAM if VCC fails 1.25 V threshold detector for power loss or general purpose voltage monitoring These features are pin−compatible with the industry standard power−supply supervisors. Short−circuit and thermal protection have also been added. The ASM690A / ASM802L / ASM805L generate a reset pulse when the supply voltage drops below 4.65 V and the ASM692A / ASM802M generate a reset below 4.40 V. The ASM802L / ASM802M have power−fail accuracy to ±2%. The ASM805L is the same as the ASM690A excep...