ZTL431BQFTA

Overview

The ZTL431BQFTA is a three-terminal adjustable precision shunt regulator from Diodes Incorporated, designed for automotive applications. It operates within an ambient temperature range of -40°C to +125°C and features a reference voltage tolerance of 0.5% at +25°C. The device supports an output voltage range from VREF (2.5V) up to 20V, set by external resistors. It provides a sink current capability between 1mA and 100mA with a typical dynamic output impedance of 0.2Ω. Packaged in a surface-mount SOT23-3 configuration, it is AEC-Q100 qualified and RoHS compliant.

Feature Summary

• AEC-Q100 qualified for automotive environments with PPAP capability
• Adjustable output voltage programmable via two external divider resistors
• High initial accuracy with 0.5% reference voltage tolerance at +25°C
• Excellent temperature stability across the full industrial operating range

Applications

• Optocoupler linearization
• Linear regulators
• Improved zener replacement
• Variable references

Procurement Notes

Verify that the specific part number matches the required grade B tolerance and SOT23 package configuration. Confirm compliance with automotive change control requirements if applicable. Ensure the ordering suffix corresponds to the desired tape and reel packaging specifications. Cross-reference the manufacturer's latest datasheet for any updates on marking codes or pin assignments before finalizing procurement.

Selection Notes

Select this component when high precision and automotive reliability are required. The Grade B designation ensures tighter initial accuracy compared to standard grades. Consider the maximum cathode voltage limit of 20V during circuit design. Verify stability boundary conditions regarding capacitive loads to prevent oscillation in the feedback loop.

Part Context

This device belongs to the ZTL431/BQ family of adjustable shunt regulators. It serves as an automotive-compliant alternative to standard TL431 devices, offering similar functionality but with enhanced qualification standards. The 'B' indicates the 0.5% tolerance grade, while 'Q' denotes automotive qualification. It shares electrical characteristics with the ZTL432 series but utilizes a different pinout in specific packages.

Replacement Considerations

Functionally equivalent to the TL431/TL432 family, except for the maximum operation voltage limitation. For direct replacements, verify that the substitute component meets the -40°C to +125°C temperature range and maintains the 0.5% initial tolerance requirement.