LM431BCM3X

Voltage Reference Overview

The LM431BCM3X is a three-terminal adjustable precision Zener shunt regulator manufactured by Texas Instruments. It operates within an output voltage range of 2.495 V to 37 V and provides initial accuracy options of 0.5%, 1%, or 2%. The device features a maximum shunt current of 100 mA and a series reference input voltage maximum of 37 V. It functions reliably across a temperature range from 0°C to 70°C. The component is housed in a surface-mount SOT-23-3 package, designed for compact circuit integration.

Voltage Reference Feature Summary

• Provides adjustable precision voltage regulation via a three-terminal shunt architecture
• Ensures stable performance with guaranteed temperature stability over the operating range
• Offers selectable initial accuracy levels to meet specific circuit tolerance requirements

Voltage Reference Applications

• Precision voltage reference sources in analog signal processing circuits
• Programmable power supply feedback loops requiring stable shunt regulation
• Battery-powered equipment utilizing low-power voltage monitoring applications

Voltage Reference Procurement Notes

Verify the specific accuracy grade (0.5%, 1%, or 2%) required for your design, as the base part number may denote a family rather than a single tolerance. Confirm the commercial temperature range (0°C to 70°C) aligns with your environmental constraints. Ensure the SOT-23-3 footprint matches your PCB layout. Cross-reference the datasheet revision to confirm pinout compatibility with existing designs.

Voltage Reference Selection Notes

Select this component when a compact, adjustable shunt regulator is needed for voltage referencing or simple regulation tasks. Consider the 100 mA current limit for load requirements. Evaluate the available accuracy grades against your circuit's error budget. Compare thermal performance if operation exceeds the commercial range, as other variants may offer extended temperature specifications.

Voltage Reference Part Context

This device belongs to the LM431 family of adjustable precision Zener shunt regulators. It serves as a direct functional replacement for legacy TL431 components in many designs. The LM431 series is widely used in power management applications due to its reliability and precise voltage control capabilities. It integrates a bandgap reference and error amplifier into a small surface-mount package.

Voltage Reference Replacement Considerations

Direct substitutes include LM431BIM3X/NOPB and LM431CIM3X/NOPB, which share the same package and electrical characteristics but may differ in accuracy grade or temperature rating. Verify that any alternative maintains the 37 V maximum input voltage and 100 mA current capability.