Hlf LM723 Voltage Regulator IC

The 723 voltage regulator is commonly used for series voltage regulator applications. It can be used as both positive and negative voltage regulator. It has an ability to provide up to 150 mA of current to the load, but this can be increased more than 10A by using power transistors. It also comes with comparatively low standby current drain, and provision is made for either linear or fold-back current limiting. LM723 IC can also be used as a temperature controller, current regulator or shunt regulator and it is available in both Dual-In-Line and Metal Can packages.The input voltage ranges from 9.5 to 40V and it can regulate voltage from 2V to 37V.

Features of 723 Voltage Regulator

Internal Block Diagram

723 Voltage Regulator Internal Block Diagram

The internal working can be explained by dividing it into two blocks, the reference voltage generatorand the error amplifier. In the reference voltage generator, a zener diode is being compelled to operate at fixed point (so that zener output voltage is a fixed voltage) by a constant current Source which comes along with an amplifier to generate a constant voltage of 7.15V at the Vref pin of the IC.

As for the error amplifier section,it consists of an error amplifier, a series pass transistor Q1 and a current limiting transistor. The error amplifier can be used to compare the output voltage applied at Inverting input terminal through a feedback to the reference voltage Vref applied at the Non-Inverting input terminal.These connections are not provided internally and so has…