78xx (sometimes L78xx, LM78xx, MC78xx...) is a family of self-contained fixed linear voltage regulator integrated circuits. The 78xx family is commonly used in electronic circuits requiring a regulated power supply due to their ease-of-use and low cost.

The LM78XX series of three-terminal positive regulators is available in the TO-220 package and with several fixed output voltages, making them useful in a wide range of

到此，只需要记住7800系列稳压器可以输出稳定正电压，且Vxx=XX；1脚为输入，3脚为输出，2脚为公共端（也就是地）即可。 如图4 (a)所示的是7800系列最基本，最简单的应用电路，其中C1，C2的参数均来自7800系列的数据手册。

lm78xx内部结构lm78××系列三端稳压器的输出为固定电压值，根据封装不同，输出电流最大可达1a或3a，通常改善输出阻抗两个数量级，并且降低静态电流的同时实现限流功能，以限制峰值输出电流在安全值范围内。当内部功耗超出散热范围时，热关断电路启动，防止芯片过热而损坏。

LM78xx http://www.hgsemi.com.cn 1/11 2018JAN 三端固定正稳压电路 产品说明 LM78xx系列是用于各种电视机、收录机、电子仪器、设备的稳 压电源电路。品种有LM7805/06/08/09/10/12/15/18/24 。 采用三引线带散热片塑料TO-220 和TO-263封装形式。 主要特点： 输出电流大，IOMAX=1.2A。

78xx，又被稱作L78xx、LM78xx、MC78xx...等，是一種固定式電壓輸出線性電壓調節器的集合。通常被用在需要穩定電源的電路中，具有便利性（易於使用）且低成本的優點。

The LM78XX series of three-terminal are available in the TO-220/D-PAK package and with several voltages, making them useful in a wide range of applications. employs internal current limiting, thermal shut-down protection, making it essentially indestructible. If adequate provided, they can deliver over 1A output current.

The MC78XX/LM78XX/MC78XXA series of three terminal positive regulators are available in the TO-220/D-PAK package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut down and safe operating area protection, making it essentially indestructible.

The LM78XX series of three terminal regulators is available with several fixed output voltages making them useful in a wide range of applications. One of these is local on card regulation, eliminating the distribution problems associated with single point regulation.

78系列线性电压调节器，又被称作78xx线性电压调节器，是一种固定式电压输出线性电压调节器的集合。 通常被用在需要稳定电源的电路中，具有便利性（易于使用）且低成本的优点。 xx指的是其输出电压，例如LM7812的输出电压为12伏特。 此种调节器输出之电压相对于接地点为高，故被称作正电压型调节器。 可以和负电压型调节器LM79xx搭配使用，以同时提供电路正负电压。 78xx系列的集成电路一般有三个接入端，通常使用TO-220封装，也有使用小型SMD贴片式封 …