How To Use Transistor As A Switch In Circuit Breaker Circuit Diagram How to switch a motor on and off using a low voltage signal. Here we switch a 50V motor on and off using a 5V output pin from an Arduino. You can use a tra When the switching signal is low (0V), the transistor turns off, and the LED is off. Transistor Switch Applications. Transistor switches find applications in various electronic circuits and systems, such as: Relay drivers: Transistors can drive relays, allowing low-power control signals to switch high-power loads. A transistor switch is used for opening or closing the circuit, which means we use a transistor is used as a switch in electrical devices only for low-voltage application devices due to their low power consumption. The transistors work as same as the switch when is it in cutoff and saturation regions.
Let's see how to use them as switches. nMOS Transistor as a Switch. An nMOS transistor works like this: When a voltage higher than the transistor's threshold voltage (V TH) is applied between the gate and the source, a current can flow from the drain to the source, making the transistor work as a closed switch. NPN and PNP transistor is same but differ in terms of their biasing and power supply polarity. 5.2.2 Transistor as a Switch: If either the circuit uses the BJT transistor as a switch, then the biasing of the transistor, NPN or PNP is arranged to operate the transistor at the both sides of the I-V characteristics curves shown below. Practical Examples of Transistor as a Switch Transistor to Switch the LED. As discussed earlier, the transistor can be used as a switch. The schematic below shows how a transistor is used to switch the Light Emitting Diode (LED). When the switch at the base terminal is open, no current flows through the base so the transistor is in the cutoff
Working of Transistor as a Switch Circuit Diagram
A low power signal across base/emitter terminal allows the transistor to switch a comparatively high power load across its collector terminal. For MOSFETs these are designated as Gate, Source, Drain. A low power signal across Gate/Source terminal allows the transistor to switch a comparatively high power load across its collector terminal. Darlington Transistor Switch; Sometimes, you'll use multiple switching transistors to switch the load voltage or current directly since the transistor's Direct Current gain is low. Hence, you'll use an input transistor to turn off and on a larger current that handles the output transistor.
