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On which leg of a transistor is the load placed?
Transistors typically have one round side and one flat side. If the flat side is facing you, the Emitter leg is on the left, the Base leg is in the middle, and the Collector leg is on the right (note: some specialty transistors have different pin configurations than the TO-92 package described above).
How are transistors connected in series?
Two NPN transistors can be connected in series with the collector of the lower transistor connected to the emitter of the upper transistor, figure 4, which provides a way to switch off the load from two different signals. Either input can turn off the load but both need to be on for the load to be on.
How do you control a transistor?
Add a Switch to Control the Transistor To turn on the transistor, you need a voltage difference between the base and the emitter of at least 0.7V. Since the emitter is attached to ground, that means any voltage over 0.7V applied to the base will turn the transistor on.
Can transistor be connected in parallel?
Bipolar Transistors (BJTs) can be connected in parallel if balancing resistors are placed in series with the emitter. BJTs generally tend to become more conductive as their temperature increases.
Can you put two transistors in parallel?
Connecting transistors in parallel is a process in which the identical pinouts of two or more transistors are connected together in a circuit in order to multiply the power handling capacity of the combined parallel transistor set.
How is a transistor set up as a switch?
The setup to set the transistor up as a switch is shown in the diagram below: The output of the device that outputs a current will be connected to the base of the transistor. The load will be connected to the collector as well as the positive DC voltage for NPNs. The emitter will connect to ground.
Why do you need a transistor in a circuit?
Transistors are devices that can amplify a signal in a circuit. If a signal in a circuit is too weak, it may not be enough to provide power to turn or or drive the load for a circuit.
How much voltage do you need to turn on a transistor?
To turn on the transistor, you need a voltage difference between the base and the emitter of at least 0.7V. Since the emitter is attached to ground, that means any voltage over 0.7V applied to the base will turn the transistor on.
How are transistors used to control high current loads?
You can use transistors from circuits like these. For example, you might put a transistor on the output pin of a 555 timer IC (which produces a variable timing pulse), or a shift register IC (which allows you to produce multiple control signals in parallel) to control high current loads from those devices.