TL431BW5-7

Overview

The TL431BW5-7 is an adjustable precision shunt regulator manufactured by Diodes Incorporated, housed in a SOT25 surface-mount package. It provides a reference voltage tolerance of ±0.5% at 25°C and operates within a temperature range of -40 to +125°C. The device supports an output voltage range from 2.5V to 36V via external resistors, with a cathode current capability between 1mA and 100mA. It features low output noise and a typical dynamic output impedance of 0.2Ω.

Feature Summary

• Adjustable output voltage settable between 2.5V and 36V using two external divider resistors
• High initial accuracy with a reference voltage tolerance of ±0.5% for the B grade
• Low output noise and excellent temperature stability across a wide operating range

Applications

• Opto-Coupler Linearisers
• Shunt Regulators
• Improved Zener replacements
• Variable Reference circuits

Procurement Notes

Verify component authenticity through authorized channels as this part may be obsolete or superseded. Confirm that the specific ordering suffix matches the required package type and tolerance grade. Ensure compliance with RoHS and halogen-free requirements if applicable to the design. Review the manufacturer's datasheet for absolute maximum ratings before integration.

Selection Notes

Select the TL431BW5-7 when high precision and low noise are critical for the application. The B grade offers tighter initial tolerance compared to the A grade. Consider the SOT25 package dimensions for PCB layout constraints. Evaluate thermal resistance and power dissipation limits based on the expected ambient temperature and load conditions.

Part Context

This component belongs to the TL431/TL432 family of three-terminal adjustable shunt regulators. It serves as a direct replacement for standard Zener diodes where improved performance is needed. The device integrates a bandgap reference, error amplifier, and output transistor to provide stable regulation.

Replacement Considerations

Diodes Incorporated recommends using the AS431 or AS431H family instead of new designs utilizing the TL431 series.