TL431BCDM

Overview

The TL431BCDM is a precision programmable three-terminal shunt voltage regulator manufactured by Microsemi Corporation. It provides an adjustable output voltage ranging from 2.5V to 36V, set via two external resistors. The device features an initial voltage reference accuracy of 0.4% and operates within a temperature range of 0°C to 70°C. It supports a cathode current sink capability from 1mA to 100mA with a typical dynamic impedance below 100mΩ. Packaged in an 8-pin Plastic SOIC (DM) surface-mount format, it serves as a direct replacement for industry standard TL431 devices.

Feature Summary

• Offers high-precision voltage regulation with an initial tolerance of 0.4%
• Provides low output impedance for improved load regulation
• Features low output noise characteristics
• Supports direct pin-to-pin compatibility with standard TL431 components

Applications

• Feedback path control in switching power supplies
• Over-voltage protection (OVP) crowbar circuits
• Reference source for A/D and D/A converters
• Zener diodes with improved turn-on characteristics

Procurement Notes

Verify component authenticity through authorized channels due to obsolete status. Confirm package integrity upon receipt, as the unit utilizes a plastic SOIC housing. Ensure compliance with RoHS transition DC: 0440 requirements if applicable to your manufacturing standards. Cross-reference datasheet specifications against legacy documentation to validate performance parameters before integration into existing designs.

Selection Notes

Select this component when precise voltage referencing is required within industrial temperature limits. The 0.4% accuracy suits applications demanding tight tolerance without requiring higher-cost alternatives. Verify that the operating environment remains within the specified 0°C to 70°C range. Consider the 8-pin SOIC footprint during PCB layout planning to ensure adequate clearance for thermal dissipation and soldering processes.

Part Context

This part belongs to the TL431 series of precision programmable references produced by Microsemi's Integrated Products Division. The 'B' suffix denotes the 0.4% initial accuracy grade, while 'DM' indicates the 8-pin Plastic SOIC surface-mount package. This specific variant is designed for general-purpose voltage regulation tasks where stability and accuracy are prioritized over extreme environmental resilience.

Replacement Considerations

The TL431BCDM is a direct pin-to-pin replacement for the industry-standard TL431 and TL1431. Designers should verify that substitute components maintain equivalent electrical characteristics, particularly regarding the 0.4% initial accuracy and operating temperature range, to ensure circuit stability.

FAQ

What is the minimum cathode current required for operation?

The device requires a minimum cathode current of 1mA to function correctly within its specified parameters.

How is the output voltage adjusted?

The output voltage is programmable using two external resistors connected between the cathode, reference, and anode terminals.