Capacitor step-down voltage stabilized power supply circuit diagram

If the capacity of capacitor C1 is doubled, the output current can be nearly doubled, but it cannot be too large. If the output ripple is large, an analog voltage regulator such as 7805/317 can be connected behind it. Changing the value of R3 can change Output voltage. The marked output current is the maximum output current. The triac B1 can be 1A. The power supply can be short-circuited. If you can ensure that the capacitor C1 is connected to the live wire, you can touch it with your hands. Originally, this power supply is for people Provided by non-contact small appliances, as long as the non-polar capacitor C1 has enough voltage resistance, it will be fine for long-term use. In principle, this is a parallel voltage stabilizing circuit with an input voltage of 220V. The voltage drops on C1. If the output current is Large, you can increase the capacity of C1. I once increased it to 2UF and it can be used normally. I also tried 4UF. When pulling out and plugging in the plug, the sparks were too big and I stopped using it. I used the thyristor shown in Figure 1. and 431 are not damaged. In fact, since E1 is 470 times that of C1, even if the AC peak value is more than 300 volts at the moment of connection, there will be no high voltage on E1. The power is easy to calculate. A 1UF capacitor is suitable for 50HZ. The capacitive reactance is 3.15k, the output current is estimated: 200V/3000 ohm, the current is about 60MA, if half-wave rectification, the current is only half. About 30MA