Touch on-off switch

Description: A touch on/off switch circuit is designed using two interconnected sensitive gate SCRs. When one SCR is activated, it forces the other SCR to turn off, creating a toggling effect that allows for an on/off condition for each of the LEDs connected to the SCR anodes. To activate LED1 while deactivating LED2, the "A" terminal must be touched. Conversely, touching the "B" terminal will turn LED1 off and activate LED2. It is also possible to touch both terminals simultaneously, which will cause both SCRs to turn on. To reset the circuit to its original one-on/one-off state, the DC power source must be momentarily interrupted. Additional circuitry can be integrated into the anode circuit of either or both SCRs to utilize the on/off functionality of the touch switch.

The touch on/off switch circuit employs two sensitive gate Silicon Controlled Rectifiers (SCRs), which are semiconductor devices that can control current flow. The SCRs are arranged in such a way that they are mutually exclusive; when one SCR is triggered, it conducts and turns on, while simultaneously turning off the other SCR. This arrangement enables a simple toggling mechanism for controlling the state of connected LEDs.

The circuit is initiated by applying a touch to the designated terminals. When the "A" terminal is touched, the first SCR is triggered, allowing current to flow through LED1, illuminating it, while simultaneously preventing current from flowing through LED2 by turning off the second SCR. Conversely, touching the "B" terminal activates the second SCR, turning on LED2 and turning off LED1. This behavior allows for a straightforward user interface, where the user can toggle between two states simply by touching the respective terminals.

In addition to the basic functionality, the circuit can be reset to its initial state by momentarily interrupting the DC power supply. This feature is useful for returning the system to a known state, especially in situations where the touch controls may have been activated unintentionally or require recalibration.

For enhanced functionality, additional circuitry may be integrated into the anode circuits of the SCRs. This could include various components such as relays, additional LEDs, or other devices that can be controlled by the on/off state of the SCRs, thereby expanding the application potential of the touch switch circuit in various electronic systems. The design offers versatility and ease of use, making it suitable for a range of applications where simple touch-based control is desired.A Touch On/Off Switch is desired, this circuit fills the bill. Two sensitive gate SCRs are interconnected, so that when one of the devices is turned on, the other (if on) is forced off. That toggling effect gives an on/off circuit condition for each of the LEDs in the SCR-anode circuits.

To turn LED1 on and LED2 off, simply touch the "A'' terminal, and to turn LED1 off and LED2 on, the "B" pick-up must be touched. It is possible to simultaneously touch both terminals, causing both SCRs to turn on together. To reset the circuit to the normal one-on/one-off condition, momentarily interrupt the circuit's dc power source. Additional circuitry can be connected to the anode circuit of either or both SCRs to be controlled by the on/off function of the touch switch.