LM397MF

Overview

The LM397MF is a single general-purpose voltage comparator manufactured by Texas Instruments. It operates from a single or split power supply with a wide voltage range of 5 V to 30 V. The device features an open-collector output stage, allowing connection to external resistors for level shifting and direct interfacing with TTL, CMOS, and other logic families. Key electrical characteristics include a low quiescent current of 300 µA, input bias current of 7 nA, and input offset voltage of ±2 mV. The propagation delay is 440 ns with a 50 mV overdrive. It is housed in a space-saving 5-pin SOT-23 package.

Feature Summary

• Supports single or dual power supply configurations within a wide voltage range
• Features open-collector output for flexible logic interfacing and level translation
• Provides low power consumption with minimal quiescent current draw
• Ensures high precision through low input bias and offset currents

Applications

• General-purpose voltage comparison circuits
• Logic level translation between different voltage domains
• Threshold detection systems
• Over-voltage protection monitoring

Procurement Notes

Verify the specific suffix 'MF' against the manufacturer's latest datasheet to confirm pinout compatibility and package dimensions. Ensure the operating temperature range meets system requirements, as industrial variants may differ. Cross-reference the part number with official Texas Instruments documentation to validate RoHS compliance status and any recent product change notifications before finalizing procurement specifications.

Selection Notes

Select this component when a low-cost, single-channel comparator with wide supply voltage tolerance is required. The SOT-23 package suits applications with strict space constraints. Consider the open-collector output requirement for pull-up resistor implementation. Evaluate if the 440 ns response time aligns with signal processing speeds. Verify that the input common-mode range covers the expected signal levels relative to the supply voltage.

Part Context

The LM397 series represents a legacy line of general-purpose comparators originally developed by National Semiconductor and continued by Texas Instruments. The LM397MF variant specifically utilizes the SOT-23-5 surface-mount package, offering a compact footprint compared to traditional DIP packages. This family is designed for cost-sensitive applications requiring reliable analog-to-digital conversion interfaces without complex digital control overhead.

Replacement Considerations

The TL331 is a documented pin-compatible alternative within the Texas Instruments portfolio. Verify functional equivalence regarding offset voltage and propagation delay when substituting.