2.495 V floor, adjustable up to 36 V
Its internal reference is set at 2.495 V minimum, and with two external resistors the output can be programmed anywhere from that floor up to 36 V maximum. The ±1% tolerance on the reference voltage gives tighter output regulation than the standard ±2% grade — useful when the feedback divider in a power supply or the bias network in an optocoupler loop needs a known starting point. The part sinks up to 100 mA at the cathode pin, which sets the headroom for driving an LED in an isolated feedback loop or for pulling down a sense node in a linear regulator. The minimum cathode current is 600 µA — below that the shunt stops regulating, so the bias resistor must be sized to keep at least 600 µA flowing even at the lowest input voltage.
SOT-23-3 — footprint and thermal note
The SOT-23-3 package (also listed as TO-236-3 / SC-59) is a three-lead surface-mount case. The thermal resistance from junction to ambient is dominated by the copper area on the cathode tab pad — for a 100 mA load, keep the trace width generous and avoid routing under the body to let the heat spread.