Simple single button 555 bistable switch design

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Using the common 555 time base integrated circuit (555 time base circuit, is a circuit that combines analog circuit and digital circuit skillfully; 555 time base circuit can use 4.5~15V separate power supply, and can also be used with other The operational amplifier and TTL circuit share the power supply; a single 555 time base circuit can provide more accurate timing time of nearly 15 minutes; the 555 time base circuit has a certain output power, the maximum output current is up to 200mA, and can directly drive the relay and small Loads such as motors, indicator lights and horns.) bistable switches have the advantages of simple wiring, reliable operation and large output current. They can directly drive relays. Relays are an electronic control device with control system (also called input circuit). And the controlled system (also known as the output loop), usually used in automatic control circuits, it is actually an "automatic switch" that uses a small current to control a large current. Therefore, it automatically adjusts in the circuit. , safety protection, conversion circuit, etc..) Class load, to achieve a load switch with a touch button.
The circuit is shown in Figure 1. When the circuit is just energized, the presence of C1 causes IC (555) 6 to obtain a positive pulse, and its 3 pin outputs a low level. At this time, there is no voltage on C2. Press the touch button S, the "0" level on C2 acts on the 2 pin of the IC, the 3 pin flips to the high level, and the C2 is charged through R3. After S is released, C2 is charged to Vcc, and the 2 and 6 pins of the IC are biased by 1/2Vcc by R1 and R2, and the high state of the 3 pin remains unchanged. Press S again, the voltage on C2 makes the IC6 pin voltage greater than 2/3Vcc, and the 3 pin flips to low level. After S is released, the voltage on C2 is discharged through R3 and IC3 pins. The voltage of pins 2 and 6 is still 1/2Vcc, and the state of low level of 3 pins can be maintained. It can be seen that each time S is pressed, the IC3 pin is changed in height and low level.
This bistable switch can realize the conversion of IC3 pin high and low level as long as the time of each button is less than 1 second. However, if you hold down S, the IC3 pin changes continuously.