Three-terminal adjustable DC voltage stabilized power supply circuit

There are many varieties of three-terminal adjustable integrated voltage regulators. The three-terminal refers to the voltage input terminal, the voltage output terminal and the voltage adjustment terminal. The positive voltage refers to
the output positive voltage. , Internationally popular positive voltage output regulators include LM117/217/317 series, I, M123 series, LM140 series, LM138 series
and LM150 series, etc. Figure 12-24 shows the LM317 three-terminal adjustable DC regulated power supply circuit, a DC power supply with continuously adjustable output voltage
, full-wave rectification, and capacitor filtered DC power supply. The secondary side of the AC power transformer adopts symmetrical double secondary, and the output DC voltage is
0.9 times the voltage on the secondary side of the transformer.
    LM317 is a three-terminal positive voltage regulator. Its output voltage is adjustable, the voltage stabilization accuracy is high, and the output ripple is small. The general output voltage is 1.2~5~
35V, and the maximum load current is 1.5A. The circuit is equipped with overcurrent protection, chip overheating protection and adjustment tube safe working area protection. Its working
temperature is 0~150℃.