TL1431CD

Overview

The TL1431CD is a precision programmable shunt voltage reference manufactured by Texas Instruments, housed in an 8-pin SOIC package. It provides an adjustable output voltage ranging from approximately 2.5V to 36V using two external resistors. The device features a typical dynamic output impedance of 0.2Ω and supports a cathode sink current range from 1mA to 100mA. Characterized for commercial operation between 0°C and 70°C, it offers an initial voltage tolerance of 0.4% at 25°C.

Feature Summary

• Adjustable output voltage settable between 2.5V and 36V via external resistive divider
• High precision with 0.4% initial voltage tolerance and low temperature drift
• Fast turn-on characteristic suitable for Zener diode replacement applications
• Internally compensated for stability without requiring an output capacitor

Applications

• Secondary side regulation in flyback switching power supplies
• Adjustable voltage and current referencing circuits
• Voltage monitoring systems
• Comparators with integrated reference

Procurement Notes

Verify the specific suffix 'CD' corresponds to the commercial temperature grade (0°C to 70°C) and SOIC-8 package configuration. Confirm that the ordering part number matches the required tolerance class and packaging format before finalizing procurement specifications.

Selection Notes

Select this component when a precise, adjustable shunt reference is required within the commercial temperature range. Ensure the application circuit maintains a minimum cathode current of 1mA for proper regulation and verify that the load capacitance remains within the stability boundary conditions defined in the datasheet.

Part Context

The TL1431 series serves as a versatile analog building block combining an accurate voltage reference with an error amplifier. It functions effectively as a single voltage reference, error amplifier, or comparator. The device is widely utilized across industrial, automotive, and computing sectors for onboard regulation and power supply control.

Replacement Considerations

TL1431QDRQ1

FAQ

Is an external output capacitor required for stability?

No, the TL1431 is internally compensated and stable without an output capacitor between the cathode and anode pins.

What is the minimum cathode current required for regulation?

A minimum cathode current of 1mA must be supplied to the cathode pin to ensure the device operates in the proper linear region for regulation.