ask for a simple circuit???

[cool]

I got a square waveform~ how can I use a simple circuit to convert it to be a dc single?? and the single must be proportional to the peak-to-peak voltage of the square waveform!! is it possilble?? :cry:

THANKS!!!!

 

[crust]

Have you considered a low pass filter?

 

[ElectricWraith]

Use an LM2907 Frequency-to-Voltage converter. It's precisely what you need.

Here's a link for the datasheet **broken link removed**

 

[Roff]

Use an LM2907 Frequency-to-Voltage converter. It's precisely what you need.

Here's a link for the datasheet **broken link removed**

This will yield a voltage proportional to frequency, which is not what you asked for. Crust's suggestion is fine so long as one of the levels of the square wave is at zero volts. If not, post a description of your waveform, including voltage levels, frequency, duty cycle, and anything else you can think of (such as what the waveform is generated by).

 

[cool]

in fact, I am doing a project for using IR to control the on/off of a lamp~

I used LM567(a tone decoder) to decode the signals received from the phototransitor, which is a square wave with a certain freq. However, I found that it was difficult to set the center frequency of it, so I give up... :cry:

Now, do you think I can only use LM2907 to do the decode part simply?? :shock:

 

[ElectricWraith]

This will yield a voltage proportional to frequency, which is not what you asked for.

Whoops, misread that bit.