3-Pin, Low-Power µP Reset Circuits

The MAX6800/MAX6801/MAX6802 microprocessor (µP) supervisory circuits monitor the power supplies in 2.85V to 5.0V µP and digital systems. They increase circuit reliability and reduce cost by eliminating external components and adjustments.

These devices perform a single function—they assert a reset signal whenever the VCC supply voltage declines below a preset threshold, keeping it asserted for a preset timeout period after VCC has risen above the reset threshold. The only difference among the three devices is their output. The MAX6801 (push/pull) and MAX6802 (open-drain) have an active-low RESET output, while the MAX6800 (push/pull) has an active-high RESET output. The MAX6800/MAX6801 are guaranteed to be in the correct state for VCC down to 0.7V. The MAX6802 is guaranteed to be in the correct state for VCC down to 1.0V.

The reset comparator in these ICs is designed to ignore fast transients on VCC. Reset thresholds are factory-trimmable between 2.63V and 4.80V, in approximately 100mV increments. These devices are available with a 1ms (min), 20ms (min), or 100ms (min) reset pulse width. Ideal for space-critical applications, the MAX6800/MAX6801/MAX6802 come packaged in a 3-pin SOT23. For a lower threshold voltage version, see the MAX6332/MAX6333/MAX6334.

Applications

* Computers * Controllers * Critical μP/μC Power Monitoring * Intelligent Instruments * Portable/Battery-Powered Equipment

* Ultra-Low 0.7V Operating Supply Voltage

* Low 4.0µA Supply Current

* Precision Monitoring of 2.85V to 5.0V Power-Supply Voltages

* Reset Thresholds Available from 2.63V to 4.80V, in Approximately 100mV Increments

* Fully Specified over Temperature

* Three Power-On Reset Timeout Periods Available (1ms min, 20ms min, 100ms min)

* Low Cost

* Three Available Output Structures: Push/Pull RESET, Push/Pull active-low RESET, Open-Drain active-low RESET

* Guaranteed RESET/active-low RESET Valid to VCC = 0.7V (MAX6800/MAX6801)

* Power-Supply Transient Immunity

* No External Components Required

* 3-Pin SOT23 Package

* Pin Compatible with MAX809/MAX810, MAX6326/MAX6327/MAX6328, and MAX6346/MAX6347/MAX6348