DESCRIPTION

The DS1705/DS1706 3.3 or 5.0 Volt MicroMonitor monitors three vital conditions for a microprocessor: power supply, software execution, and external override. A precision temperature compensated reference and comparator circuit monitors the status of VCC at the device and at an upstream point for maximum protection. When the sense input detects an out–of–tolerance condition a non–maskable interrupt is generated. As the voltage at the device degrades an internal power fail signal is generated which forces the reset to an active state. When VCC returns to an in–tolerance condition, the reset signal is kept in the active state for a minimum of 130 ms to allow the power supply and processor to stabilize.

FEATURES

• Halts and restarts an out–of–control microprocessor

• Holds microprocessor in check during power transients

• Automatically restarts microprocessor after power failure

• Monitors pushbutton for external override

• Accurate 5, 10 or 20 resets for 3.3 systems and 5 or 10 resets for 5.0 volt systems

• Eliminates the need for discrete components

• 3.3 volt 20 tolerance for use with 3.0 volt systems

• Pin compatible with the MAXIM MAX705/MAX706 in 8–pin DIP and 8–pin SOIC

• 8–pin DIP, 8–pin SOIC and 8–pin µ–SOP packages

• Industrial temperature range –40°C to +85°C