I want to build a little adapter board to connect an existing PSOC prototyping board (CY8CKIT-059) to QIIC connector (which is just I2C using JST 4-pin connectors). The QIIC standard calls for 3.3V power, but my board doesn't have that, just the USB VBUS derrived 5 Volts.
Rather than drop an LDO on my adapter, I thought I might take advantage of a spare opamp on the PSOC, but the output pins are limited to about 25 mA, I want to go higher than that. Dusting off mental cobwebs, I recall building an emitter follower with a 2N2222. (Does that part date me?) Here's the idea:
Would a using a MOSFET here instead of a bipolar have any advantage?
I've not done any surface mount before, but with JLCPCB's assembly service, it seems like time to give it a try. Is there a way for me to look up something similar the old through-hole transistor in a SMD package.