# Conversion of square wave to DC.

#### justin_555

Joined Feb 25, 2018
2
Draw the circuit to Convert square wave to DC, As the frequency increases the DC amplitude should increase.

#### Alec_t

Joined Sep 17, 2013
12,155
Welcome to AAC!
Is this school/college work?

#### AnalogKid

Joined Aug 1, 2013
9,292
Draw the circuit to Convert square wave to DC, As the frequency increases the DC amplitude should increase.
No, it shouldn't.

The DC value of a symmetrical square wave is 50% of its peak value, no matter what the frequency is. If the send half of the question is correct, then the first half is not stated correctly. The entire question is correct for a rectangular waveform that is pulse-width modulated or pulse-position modulated.

Of course it is possible to convert a frequency-modulated square wave to a DC value that increases as the frequency increases - that is what an FM radio does. Does the instructor want you to design an FM detector?

If not, there is a large difference between converting a square wave to its equivalent DC value (using a lowpass filter) and its peak DC value (using a rectifier).

Two questions for the instructor:
1. Is it a symmetrical square wave?
2. Average or peak DC value?

ak

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#### bertus

Joined Apr 5, 2008
21,453
Hello,

The average DC voltage can only change when the duty cycle of the squarewave signal changes.

Bertus

#### OBW0549

Joined Mar 2, 2015
3,566
Draw the circuit to Convert square wave to DC, As the frequency increases the DC amplitude should increase.
That's an awfully sketchy description of what you're looking for, and leaves a lot of room for (mis)interpretation. I'll make a wild guess here and assume you want a frequency-to-voltage converter, also known as a tachometer circuit.

There is no "the" circuit for a F-to-V converter; there are many, MANY possible designs. This Google Images page shows scores of possibilities.

#### GopherT

Joined Nov 23, 2012
8,012
Draw the circuit to Convert square wave to DC, As the frequency increases the DC amplitude should increase.
Is this a homework assignment or a request for s project?

#### Picbuster

Joined Dec 2, 2013
1,027
Draw the circuit to Convert square wave to DC, As the frequency increases the DC amplitude should increase.
Justin,
first step is to make a formulae of the sq wave output power input should be amplitude, offset, % on in one period and frequency.
When you observe your formulae you will detect dependencies in power which is a direct link to the output voltage.
Next step is to convert this signal into a DC.
Ask yourself the question how can I store these 'pulses' and what do I need to do so and more important what electronic component will do this for me?
So get your brand new brains out of the package and start pestering it with foresaid questions.

Picbuster