MAX6337US18D3+T

Overview

The MAX6337US18D3+T is a microprocessor supervisory circuit designed for low-voltage digital systems. It monitors the VCC supply voltage and asserts an active-low, open-drain reset signal when the input drops below a preset threshold of 1.8V. The device features a manual reset input with debounce capability and operates within a supply voltage range of 1.25V to 5.5V. It draws a typical quiescent current of 3.3µA and includes a fixed timeout period of 150ms after the supply rises above the threshold. The component is housed in a compact SOT-143-4 surface-mount package and supports operation across an extended temperature range from -40°C to +125°C.

Feature Summary

• Monitors single power supply rail with precise undervoltage detection
• Includes debounced manual reset input for system control
• Provides active-low open-drain reset output with fixed timeout
• Operates at ultra-low quiescent current for battery efficiency

Applications

• Microprocessor (µP) power supply monitoring in embedded systems
• Battery-powered portable devices requiring low standby current
• Digital logic circuits needing reliable brown-out protection
• Industrial control systems operating in extended temperature environments

Procurement Notes

Verify the specific suffix D3 corresponds to the 1.8V threshold variant during sourcing. Confirm RoHS compliance status as indicated by the plus sign in the part number. Check manufacturer documentation for lead time variations due to potential limited availability or discontinuation notices associated with older Maxim Integrated product lines.

Selection Notes

Select this component when a single-channel voltage monitor with manual reset functionality is required. Ensure the 1.8V threshold aligns with the target system's minimum operating voltage. Consider the open-drain output requirement for pull-up resistor implementation. Verify that the SOT-143-4 package fits the PCB layout constraints compared to alternative packages like SC-70 or TDFN.

Part Context

This part belongs to the MAX633x series of ultra-low-voltage, low-power microprocessor reset circuits. The series differentiates models primarily by output type (push-pull vs. open-drain), presence of manual reset, and specific voltage thresholds. The MAX6337 specifically combines manual reset capability with an open-drain output, distinguishing it from the push-pull MAX6336 and non-reset MAX6335 variants.

Replacement Considerations

Direct substitutes include other MAX633x family members such as MAX6337US19D3+T or MAX6337US23D3+T if different voltage thresholds are acceptable. Cross-reference with MAX6335US18D3+T if manual reset is not needed. Verify pin compatibility and electrical specifications before substitution.