SPX431BM5-L/TR

Overview

The SPX431BM5-L/TR is a precision adjustable shunt voltage regulator manufactured by Sipex, functioning as an open-loop error amplifier with a highly accurate bandgap reference. It provides a nominal output of 2.495 V, adjustable via external resistors. The device operates within a supply voltage range up to 36 V and supports a maximum shunt current of 150 mA. Initial accuracy is specified at 0.5%, with a temperature coefficient of 30 PPM/°C. It features a SOT-89-3 surface-mount package and operates across an extended temperature range from -40°C to +125°C.

Feature Summary

• Provides precise bandgap reference for stable voltage regulation
• Adjustable output voltage using two external resistors
• High accuracy with low temperature drift characteristics

Applications

• Precision power supply regulation
• Voltage reference sources in measurement equipment
• Feedback control loops in switching regulators

Procurement Notes

Verify the manufacturer designation carefully, as this component has been associated with Sipex, MaxLinear, and EXAR due to corporate acquisitions. Confirm the specific datasheet version matches the required tolerance and thermal specifications. Ensure the SOT-89-3 package footprint aligns with the PCB design. Check for moisture sensitivity levels if reflow soldering is planned. Validate that the 'L' suffix does not imply a different electrical characteristic than the standard SPX431BM5 variant.

Selection Notes

Select this component when a high-precision, adjustable shunt regulator is required in a compact surface-mount form factor. It is suitable for applications demanding tight initial accuracy and low temperature coefficients. Consider the 150 mA maximum shunt current limit for load requirements. The wide operating temperature range makes it appropriate for industrial environments. Ensure the input voltage does not exceed the maximum rating of 36 V.

Part Context

The SPX431 series belongs to a family of three-terminal adjustable shunt regulators derived from the Zener diode concept but offering superior performance. These devices act as parallel voltage references, commonly used in place of traditional Zener diodes for better stability and lower impedance. The SPX431BM5-L/TR specifically utilizes the Sipex manufacturing process known for precision analog integration.

Replacement Considerations

Direct replacements include the SPX431AM1-L/TR and SPX431LM/TR, though package differences (SOT-89-3 vs SOT-23) must be verified. Generic equivalents such as the TL431 are functionally similar but may differ in accuracy and temperature coefficient specifications.