Adjustable shunt reference in a compact SC-70-6
It provides a 2.495 V reference that can be set to any output voltage up to 36 V using two external resistors. The ±2.2% initial tolerance places this variant in the middle of the TL431 accuracy tiers — tighter than the ±2% standard grade but not as tight as the ±0.5% or ±1% precision options. For a 5 V output rail, that translates to roughly ±110 mV worst-case at 25°C before temperature drift.
100 mA output and 1 mA cathode current floor
Rated for 100 mA continuous output current, the TL431QDCKR can drive optocoupler LEDs in isolated power supplies, bias small-signal transistors, or serve as a precision shunt reference for an ADC reference input. The 1 mA minimum cathode current ensures the device stays in its linear regulation region; designs must bias it above that threshold or the output voltage drifts. The SC-70-6 package keeps the footprint small, but the thermal impedance is higher than a SOT-23; for sustained 100 mA operation, check the junction temperature against the ambient derating curve.