正负12V转正负5V线性稳压电路制作-----12v -5v power regulator

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This is the voltage converter to get the voltage of ±5V from the input voltage of ±12V. I am using the 3 terminal voltage regulator for the voltage to be changed in this unit. As the regulator, LM317 is used for the positive voltage and LM337 is used for the negative voltage. The output current can make output in 1 A.
The point of this unit making is the radiator (the heatsink) of the regulator. The regulator becomes hot when outputting the 1 A electric current and when there is not a heatsink, the regulator breaks.
The merit of the regulator of this type is what little noise occurs and is cheap and there are few use parts. The demerit is the thing with the conversion efficiency which isn't good. When outputting from 12 V to 5 V, the efficiency (the output power/input power) is 42%. Recently, the switching regulator became cheap. The number of parts increases little but in case of more than 1 A power supply, you had better use the switching regulator with the good efficiency.

这个电路将正负12V转正负5V电路，电路简单，为线性稳压电源，效率有点低，只有42%，因此不适合大电流应用，LM317如果使用TO-220封装，不装散热片情况下输出几百毫安电流就比较热了，因此最好安装上散热器。

该电路优点是加如好些二极管做保护，同时配有发光二极管做指示，方便查看，当然，如果需要输出其他电压，可以通过调整可调电阻VR1和VR2得到。

上图为做好的样式，由于电路简单，因此用万能板直接进行焊接也挺方便的。