It's a jellybean part, ideal for when you just need to add some 3.3V power in your circuit.
- ST Electronics L4931
- 3.3V, 250mA positive fixed voltage regulator
- 0.4V dropout at 250mA
- Only requires a single 2.2µF capacitor between Vout and GND (but a 0.1µF on input is a good idea)
- Pin assignments (viewed pins down; flat face toward you): 1 = Vout, 2 = GND, 3 = Vin
- TO92 through-hole transistor-like package