LM431ACZ/LFT1

Voltage Reference Overview

The LM431ACZ/LFT1 is a two-terminal adjustable shunt voltage reference manufactured by Texas Instruments, formerly National Semiconductor. It operates within an output voltage range of 2.495 V to 37 V and features an initial accuracy of 2%. The device supports a maximum shunt current of 100 mA and has a temperature coefficient of 97 ppm/°C. It is housed in a TO-92-3 through-hole package and functions within a temperature range of -40°C to +85°C.

Voltage Reference Feature Summary

• Provides precise adjustable voltage regulation via two-terminal shunt configuration
• Maintains stable reference performance across wide operating temperature ranges
• Supports high current handling capabilities for robust circuit protection

Voltage Reference Applications

• Precision voltage regulation in power supply circuits
• Over-voltage protection mechanisms
• Programmable Zener diode implementations

Voltage Reference Procurement Notes

Verify the manufacturer designation carefully, as Texas Instruments acquired National Semiconductor. Ensure the specific suffix matches your packaging requirements. Confirm RoHS compliance status with the supplier. Check for obsolescence notices given the component's age. Validate that the TO-92-3 package aligns with your PCB footprint constraints.

Voltage Reference Selection Notes

Select this component when a low-cost, through-hole adjustable reference is required. Compare the 2% initial accuracy against tighter tolerance needs. Consider the 97 ppm/°C temperature coefficient for thermal stability requirements. Evaluate the 100 mA current limit against load demands. Verify compatibility with existing TO-92-3 board layouts.

Voltage Reference Part Context

This part belongs to the LM431 series of programmable shunt regulators. Originally developed by National Semiconductor, production continues under Texas Instruments. The series is widely used for replacing fixed Zener diodes in precision applications. The LM431ACZ variant specifically offers 2% accuracy. The LFT1 suffix indicates tape and reel packaging.

Voltage Reference Replacement Considerations

Direct substitutes include LM431AIMLX/NOPB and LM431BIM3X/NOPB. Alternative packages like SOT-23 or SOIC are available from TI. Cross-reference with ON Semiconductor LM431 variants for pin-compatible options. Verify electrical specifications match before substitution.