This circuit typically uses a diode to rectify an incoming amplitude-modulated signal, followed by a low-pass filter consisting of a resistor and capacitor. The capacitor charges to the peak of the carrier pulses and slowly discharges, effectively tracing the outline of the signal's amplitude changes. It is the simplest and most common method for demodulating AM radio broadcasts.
The time constant on the envelope detector is too long, causing diagonal clipping on the fast volume transients.
Also heard as
- peak detector
Related terms
Envelope
The envelope is the smooth curve outlining the extremes of a modulated high-frequency signal.
Diode
A two-terminal semiconductor component that restricts electrical current to flow in only one direction.
Lowpass
A type of filter that allows low-frequency signals to pass while blocking higher frequencies.