What is the valley point in UJT?
The "valley point" in UJT refers to a specific point in the UJT's characteristic curve where the current through the device reaches its minimum value.
Why is UJT used as a relaxation oscillator?
UJT (Unijunction Transistor) is commonly used as a relaxation oscillator because of its unique characteristics. A relaxation oscillator is an electronic oscillator that produces a non-sinusoidal waveform such as a square, triangular, or sawtooth waveform. It generates this waveform by repeatedly charging and discharging a capacitor through a resistance.
What is the difference between UJT and diode?
A diode is connected to a resistive divider network, to form UJT. It differs from an ordinary diode UJT has three terminals but an ordinary diode has two terminals (anode and cathode).
Which type of switch is used in UJT?
UJT does not have a traditional on-off switch configuration like mechanical switches or other electronic switches. Instead, it has a unique characteristic known as negative resistance that allows it to act as a switch. When a voltage is applied to the emitter, UJT remains in an off state until the emitter voltage reaches a particular level known as the Peak Point Voltage (\(V_p\))
Why is UJT called Uni Junction?
The UJT (Unijunction Transistor) is called so because it has only one junction, which is the PN junction between the emitter and the base. The UJT is a three-layered semiconductor device with two external terminals: an emitter (E) and a base (\(B_1\)). The base region is lightly doped, and the emitter region is heavily doped. A third terminal called the base-2 (\(B_2\)), is connected to the midpoint of the base region.