Digital Electronics Notes, lectures for engineering and diploma students

SCR In Parallel

The maximum power that can be controlled by a single SCR is determined by its rated forward current and rated forward blocking voltage.

RC High-Pass Filter Circuit

Fig. 1 shows the series RC high-pass filter circuit. In such circuit, the output is taken across the resistor and practically reactance of the capacitor decrease with increasing frequency.

RLC Filter Circuit

Consider the series RLC filter circuit shows in Fig. 1(a). If a unit step function is applied, we see that

RL Filter Circuit

Simple RC circuits are not used in switching circuits, especially, in integrated circuit. However, inductors are still used, as in the case of current sweep generation, tunnel diode monostable and astable circuits.

Sequential Logic Circuits

In digital circuits, such as comparators, two 8-bit numbers may be considered to generate and output only when they are the same.

Shift Registers

A register is a device which is used to store information. Flip flops are often used to make a register.

Speed of Microprocessor

The speed of microprocessor indicates that how much it is speedy to execute different programes or instructions.

RC Feedback Oscillators

RC oscillators employ resistors and capacitors and are used to generate low or audio-frequency signals. Hence they are also known as audio-frequency (A.F) oscillators.

Pulse Generator

A device that produces an electrical discharge at regular intervals, which can be modified as needed, as in an electronic pacemaker.


The printer is an ouput device which gives the hard copy of the data or graphics stored in the memory of computer. There are two main types of printers.