In this article we will comprehensively study a transistor relay driver circuit and learn how to design its configuration by calculating the parameters through formulas. Importance of Relay Relays are one of the most important components in electronic circuits. Especially in circuits where high power transfer or mains AC load switching is involved, relays play […]
Transistor
Transistor Multivibrator Circuits [Astable, Bistable, Monostable]
A transistor or BJT multivibrator is a two-stage switching circuit that is configured in a cross-coupled manner. This allows each of the active BJT stages to be regeneratively cross-coupled with the other BJT stage, so that one switches ON when the other switches OFF, and vice versa. This cross-coupling may be set up to switch either a […]
Variable Voltage, Current Power Supply Circuit Using Transistor 2N3055
In this post I have explained how to make a simple variable power supply circuit using transistor 2N3055 and some other passive components. It includes variable voltage and variable current feature, fully adjustable. Main Specifications 1) Adjustable from 0-30V, 0-60V, and 0-100V, and 500mA to 10 Amp as per user preference 2) Short Circuit Protected […]
Unijunction Transistor (UJT) – Comprehensive Tutorial
A unijunction transistor is a 3 terminal semiconductor device which is unlike a BJT has only a single pn junction. It is basically designed to be used as a single-stage oscillator circuit for generating pulsed signals suitable for digital-circuit applications. UJT Relaxation Oscillator Circuit The unijunction transistor could be typically wired in the form of […]
50 Amp Transistor MJ11032, MJ11033 Datasheet, Pinout
If you are looking for high current transistors in the range of 50 amps with a complementary pair, then you can try these Darlington transistors MJ11032 and MJ11033. The MJ11032 transistor is a Darlington NPN power transistor while the MJ11033 is its complementary PNP transistor which is also a Darlington power BJT. Main features The […]
How to Replace a Transistor (BJT) with a MOSFET
In this post I have explained the method of correctly replacing a BJT with a MOSFET, without affecting the final outcome of the circuit. Introduction Until MOSFETs arrived in the field of electronics, transistors or BJTs to be precise ruled the power switching circuits and applications. Though even Bipolar Junction Transistors (BJTs) can not be […]





