2.495 V anchor — setting the output voltage
All output voltages above that are set by two external resistors — the divider ratio determines the regulation point, up to a 36 V maximum output.
100 mA output, 700 µA cathode — load and bias budget
Rated for 100 mA continuous output current, the TL432AQPK can bias optocouplers, drive the feedback node of a primary-side controller, or supply a low-current load. The 700 µA minimum cathode current sets the minimum bias the shunt needs to maintain regulation — below that the device drops out. Designers targeting low standby power should size the bias resistor to keep the cathode current above 700 µA across the full input voltage range.
The SOT-89-3 package (TO-243AA) with a large collector tab helps dissipate heat in high-ambient conditions.
Designers can specify this part for new BOMs without supply-chain urgency.
±1% tolerance — precision where it matters
The reference voltage tolerance is ±1%.