LM431ACZ/LFT7

Voltage Reference Overview

The LM431ACZ/LFT7 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 provides initial accuracy options of 2%, 1%, or 0.5%. The device features a temperature coefficient of 97 ppm/°C and supports a maximum shunt current of 100 mA. It functions reliably across a minimum operating temperature of -40°C and a maximum of +85°C. Packaged in a TO-92-3 through-hole format, it serves as a precision reference for linear regulation and feedback loops.

Voltage Reference Feature Summary

• Provides stable, adjustable reference voltage via two-terminal shunt configuration
• Ensures high precision with selectable initial accuracy grades
• Maintains performance stability across wide industrial temperature ranges

Voltage Reference Applications

• Linear power supply regulation
• Feedback loop compensation in switching converters
• Precision voltage monitoring circuits

Voltage Reference Procurement Notes

Verify the manufacturer designation carefully, as the component originates from National Semiconductor but is now distributed under the Texas Instruments portfolio. Confirm that the specific suffix corresponds to the required accuracy grade and packaging format. Ensure compatibility with existing thermal management designs given the through-hole package constraints.

Voltage Reference Selection Notes

Select this component when a low-cost, adjustable shunt reference is required for standard through-hole PCB layouts. Consider the 97 ppm/°C temperature coefficient for applications where moderate thermal drift is acceptable. Evaluate the 100 mA current limit against peak load requirements in the target circuit design.

Voltage Reference Part Context

This part belongs to the LM431 family of adjustable zener diodes, widely used as voltage references. Originally developed by National Semiconductor, the product line was integrated into Texas Instruments' portfolio following corporate acquisition. The LM431 series remains a standard solution for cost-sensitive analog reference applications requiring adjustable output voltages.

Voltage Reference Replacement Considerations

Direct substitutes include the LM431BIZ/LFT7 for tighter accuracy specifications and the LM431AIMX/NOPB for surface-mount implementations. Verify pinout compatibility and thermal characteristics when transitioning between different package types or manufacturers within the same functional family.