Automatic voltage regulator power supply circuit composed of integrated circuit and two-way thyristor - Power Circuit - Circuit Diagram

The power circuit is shown in the figure. Components such as ICl form a voltage comparator. When the grid voltage changes, the DC voltage after rectification and Cl filtering is also changed by VD. This varying voltage is compared as a sampled voltage to a stable DC voltage. As the grid voltage changes from low to high, the voltage comparators A, B, and C gradually output low levels.

In the figure, T1: autotransformer; Y2: sampling transformer; ICl: LM339; IC2: CD4070; IC3: TWH9205; IC4 ~ IC7: TWH8778; IC8: W7806; resistance Rl, R2: 150Ω; R3 ~ R9: 10kΩ; Rl0 ~Rl3: 20kΩ; R14: 20kΩ, 4W; thermistor RT: 47kΩ; RPl: 680Ω; Rp2: 4.7kΩ; Rp3: 100kΩ; Cl: 47μF16V; C2: 0.1μF; C3: 100μF16V; VD1: lN4002; VD2: 2CW54; thyristor SCRl ~ SCR4 can be reasonably selected according to the size of the load power.