Electronic Circuits and Circuit Design Information

- a potpourri of basic electronic circuits, circuit ideas, and formulae for anyone undertaking electronic circuit design

The exact configuration of an electronic circuit is not always easy to remember, and even then there are associated electronic circuit design formulae to calculate the various circuit values. This section of the Radio-Electronics.Com website contains information about basic electronic circuits, building blocks, along with the relevant formulae to provide a unique reference on the web for anyone undertaking electronic circuit design.

This section is organised by the chief component in the circuit. Thus a filter using an operation amplifier would come under the operational amplifier section, and a transistor radio frequency amplifier would come under the transistors section and a pin diode attenuator would be found in the diodes section.

Resistor circuits
Resistors are the most widely used components in electronic circuits. Although very simple in concept they are key to the operation of many circuits. They can be used in a variety of ways to produce the requried results.
- Resistors in parallel
- Resistor attenuator circuits

Resistor capacitor (RC) circuits
RC or resistor capacitor circuits are used in a number of applications and may be used to provide simple frequency dependent circuits.
- Twin T notch filter

LC filter circuits
Using inductors and capacitors a whole variety of filters can be designed and made. These include low pass, high pass and band pass filters
- Low pass LC filter
- High pass LC filter
- Band pass LC filter

Diode circuits
The diode is one of the most elementary semiconductor devices. It essentialy allows current though the device in one direction. Using this facet of the diode there are many uses, but there are also other facets of its nature that enable to to be used in other applications as well.
- Simple PIN diode RF switch
- Constant impedance pin diode attenuator
- Power supply current limiter
- Diode voltage multiplier
- Single balanced diode mixer
- Double balanced diode mixer

Transistor circuits
- Two transistor amplifier circuit with feedback
- Transistor active high pass filter
- Transistor current limiter for power supplies
- Transistor crystal oscillator

SCR, Diac and Triac Circuits
SCR overvoltage crowbar circuit

Operational amplifier circuits
Operational amplifiers are one of the main building blocks these days used in analogue electronics. They are not only easy to use, but they are plentiful, cheap and offer a very high level of performance.
- Operational amplifier basics
- Inverting amplifier
- High input impedance inverting amplifier
- Summary of op-amp gain
- Non-inverting amplifier
- High pass filter
- Low pass filter
- Band pass filter
- Variable gain amplifier
- Fixed frequency notch filter
- Twin T notch filter with variable Q
- Multivibrator oscillator
- Bistable multivibrator
- Comparator
- Schmitt trigger

Digital logic circuits
Logic circuits consisting of building blocks including AND and OR and NAND and NOR gates for the basis of today's digital circuitry that is used in widely in electronics. Trigger, bistables, flip flops,etc, are also widely sued and can be made up from the basic building blocks.
- Logic truth table
- Hints and tips on designing and laying out digital or logic circuits
- Using inverters to create other functions
- A divide by two frequency divider using a D-type flip-flop
- An R S flip flop using two logic gates
- An edge triggered R S flip flop using two D types
- An electronically controlled inverter using an exclusive OR gate