PWM to analog voltages ??

[hameeds01]

Hello guys
I would appreciate if someone could help me. I need to convert PWM into analog voltage @ 5ma then I want to read it via ADC,


I/P :::::: PWM = 300Hz, duty cycle 0 – 100%, 12V @ 5Amps.

Required::: Circuit which can perform this task (PWM ---> analog voltage).

O/P:::::: analog voltage 0 – 12v @5ma corresponding to the duty cycle.

Regards
Engineer hameed

 

[zx_sa]

PWM to Analogue Voltage is a basic process: Low pass filtering.

You need to pass the PWM signal through a low pass filter (normal RC will do in most cases) where the cut off frequency is maybe at about 200Hz.

In order to satisfy your 5mA requirement, you will need a small value for the resistor in the RC network. I suggest perhaps 48 ohm. Your C will then work out to be roughly 100uF which is a common value.