Package and mounting
The 100 mA output current capability is unusually high for a shunt reference — it can directly bias an optocoupler LED in a feedback loop or power a small load without a buffer transistor. Minimum cathode current is 1 mA, so the part stays in regulation down to light loads. The commercial temperature range (0°C to 70°C) fits indoor equipment, bench supplies, and office electronics — not an engine bay or a rooftop radio.
How it compares to a series reference like the LM4132
The LM4132AMF-4.1/NOPB is a fixed 4.096 V series reference in a surface-mount SOT-23 package with ±0.05% tolerance and a 20 ppm/°C drift. The TL1431CLP is a shunt reference — it works like a programmable Zener, not a three-terminal regulator. The shunt topology means it can regulate voltages above its own set point (up to 36 V) and sink rather than source current. The trade-off: the TL1431CLP's ±0.4% tolerance is eight times looser than the LM4132's, and its 0°C to 70°C range is narrower than the LM4132's -40°C to 125°C. If your board needs a precise fixed voltage over temperature, the LM4132 wins. If you need an adjustable high-voltage reference or a current-sinking regulator, the TL1431CLP is the right topology.
Lifecycle and sourcing — active, no LTB pressure
The TL1431CLP is listed as Active with ROHS3 compliance. No end-of-life notice, no last-time-buy deadline.