Unijunction transistor delay circuit

Published:2011/7/4 19:30:00 Author:Christina | Keyword: Unijunction transistor, delay circuit | From:SeekIC

The delay circuit which is composed of the unijunction transistor is as shown in figure 1. When the power supply is connected, the +28V power adds to the unijunction transistor delay circuit through the normally closed contact point of the conversion contact point K1-1 of the relay K1, so the delay circuit starts working. The capacitance C is charged through RP1, when the charging voltage Vc of the C is the same as the peak voltage of the unijunction transistor, the VT conducts, the C discharges through VT and K1, so the discharging current is large, the relay K closes, the normally open contact point of the conversion contact point K1-1 closes, and the normally closed contact point cuts off, the power of the timing circuit turns off. Figure 1 The delay circuit



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Control_Circuit/Unijunction_transistor_delay_circuit.html

Print this Page | Comments | Reading(3)