Block Diagrams

 

Block diagrams are used to understand (and design) complete circuits by breaking them down into smaller sections or blocks. Each block performs a particular function and the block diagram shows how the blocks are connected together. No attempt is made to show the components used within a block, only the inputs and outputs are shown. This way of looking at circuits is called the systems approach.

Power supply (or battery) connections are usually not shown on block diagrams.

 

 

Audio Amplifier Block Diagram

 

Audio Amplifier Block Diagram

Block Diagram of an Audio Amplifier

 

Microphone - converts sound to an audio signal.

Pre-Amplifier - amplifies the weak signal from the microphone.

Tone and Volume Controls - adjust the nature of the audio signal.

The tone control adjusts the balance of high and low frequencies.

The volume control adjusts the strength of the signal.

Power Amplifier - increases the strength (power) of the audio signal.

Loudspeaker - converts audio signal to sound.

 

 

Radio Receiver Block Diagram

 

Radio Receiver Block Diagram

Block Diagram of a Radio Receiver

 

Aerial - picks up radio signals from many stations.

Tuner - selects the signal from just one radio station.

Detector - extracts the audio signal carried by the radio signal.

Amplifier - increases the strength (power) of the audio signal.

Loudspeaker - converts audio signal to sound.

 

 

Regulated Power Supply Block Diagram

 

Regulated Power Supply Block Diagram

Block Diagram of a Regulated Power Supply

 

Transformer - steps down 230V AC mains to low voltage AC.

Rectifier - converts AC to DC, but the DC output is varying.

Smoothing - smooth's the DC from varying greatly to a small ripple.

Regulator - eliminates ripple by setting DC output to a fixed voltage.