通晶体管增强调节器的输出电流

摘要：一个5V线性稳压器与外部晶体管（它提供了一个额外的并行路径，负载电流）提供两倍的输出电流（ 150mA至300毫安）保持5V调控的同时。
Maxim > App Notes > Automotive Power-supply circuits
Keywords: linear regulators, pass transistors Sep 24, 2004

APPLICATION NOTE 3333
Pass Transistor Enhances Regulator's Output Current


Abstract: A 5V linear regulator with external pass transistor (which provides an additional, parallel path for load current) delivers
twice as much output current (150mA to 300mA) while maintaining 5V regulation.

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 regulation while delivering more than 300mA.




Figure 1. An external pass transistor (Q1) more than doubles the output-current c