Precision shunt reference for automotive BOMs
Its defining parametric advantage over the standard TL431 is the ±0.5% tolerance on the 2.495 V reference — half the spread of the typical ±1% grade, which eliminates the need for external trim resistors in many feedback and regulation loops.
±0.5% tolerance — what it changes on the BOM
The standard TL431 is specified at ±1% or ±2% initial tolerance. For a 5 V output rail, that tightens the worst-case initial accuracy from ±50 mV to ±25 mV — enough to skip a post-assembly trim step in many designs. The cathode current range runs from 600 µA minimum to 15 mA maximum, covering the bias needs of optocoupler feedback in isolated supplies and error-amplifier loads in non-isolated regulators. The 36 V maximum output voltage suits 24 V and 48 V bus rails with margin.
Automotive qualification and package fit
The SOT-23-3 package is a three-pin footprint shared across the entire TL431 family, so the PCB layout is identical whether the BOM uses a ±0.5%, ±1%, or ±2% grade.