In Figure 1, the 5V linear regulator (U1) delivers as much as 150mA of load current when operating by itself. Operating with the external pass transistor shown (Q1), the circuit maintains 5V ...

An SCR topology transmogrifies into BJT two-wire precision current source with a self-resetting fault-current limiter.

[Kevin Darrah] wanted to make a simple 3.3V regulator without using an integrated circuit. He wound up using two common NPN transistors and 4 1K resistors. The circuit isn’t going to beat out a cheap ...

There are many cases where a power supply needs an internal current-limiter function, usually built using a current sensor, a control circuit, and a pass transistor. The current sensor itself can be a ...