General Description

The MAX6335/MAX6336/MAX6337 microprocessor (µP) supervisory circuits monitor the power supplies in 1.8V to 3.3V µP and digital systems. They increase circuit reliability and reduce cost by eliminating external components and adjustments. They also feature a debounced manual-reset input.

These devices perform a single function: they assert a reset signal whenever the VCC supply voltage declines below a preset threshold or whenever manual reset is asserted. Reset remains asserted for a preset timeout period after VCC has risen above the reset threshold or after manual reset is deasserted. The only difference among the three devices is their output. The MAX6336 (push/pull) and MAX6337 (open-drain) have an active low RESET output, while the MAX6335 (push/pull) has an active-high RESET output. The MAX6335/MAX6336 are guaranteed to be in the correct state for VCC down to 0.7V. The MAX6337 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 1.6V and 2.5V, in approximately 100mV increments. There are 15 standard versions available (2500 piece minimum-order quantity); contact the factory for availability of nonstandard versions (10,000 piece minimum-order quantity). For space-critical applications, the MAX6335/MAX6336/MAX6337 come packaged in a 4-pin SOT143.

Features

♦ Ultra-Low 0.7V Operating Supply Voltage

♦ Low 3.3µA Supply Current

♦ Precision Monitoring of 1.8V and 2.5V Power Supply Voltages

♦ Reset Thresholds Available from 1.6V to 2.5V,

   in Approximately 100mV Increments

♦ Debounced Manual Reset

♦ Fully Specified over Temperature

♦ Three Power-On Reset Pulse Widths Available

   (1ms min, 20ms min, 100ms min)

♦ Low Cost

♦ Three Available Output Structures: Push/Pull

   RESET, Push/Pull RESET, Open-Drain RESET

♦ Guaranteed RESET/RESET Valid to VCC = 0.7V (MAX6335/MAX6336)

♦ Power-Supply Transient Immunity

♦ No External Components

♦ 4-Pin SOT143 Package

♦ Pin Compatible with MAX811/MAX812 and MAX6314/MAX6315

Applications

   Pentium II™ Computers

   Computers

   Controllers

   Intelligent Instruments

   Critical µP/µC Power Monitoring

   Portable/Battery-Powered Equipment

   Automotive