Hi,

I need to generate a PWM wave and vary its duty cycle. This I will in turn feed to a FPGA. I want to chk those digital input channels.

Can someone help me out with a simple way to generate a PWM with varying duty cycle.

 

Since you posted this in the uc section, you want to create the PWM signals by using a microcontroller? Do you own a microcontroller already, or do you need help choosing one for easily creating PWM signals?

You can also create PWM signals by using ne NE555 timer IC, a quick google (555 timer circuit) should help you along the way.

 

Hi,
You should mention which microcontroller you are going to use: AVR, PIC, MSP, ST7, etc
You should also mention the language and compiler you are going to program in: mikroC, mikroBASIC, mikroPASCAL, CCS, Hi-Tech, WinAVR, IAR, etc.

 

thanks a lot,,may be I will just use a 555 timer. that should work.
I think I can vary the duty cycle in it also.

 

Yes, you can vary the duty cycle with a 555.

Give this a read, It is from a member here, Bill_Marsden:
http://forum.allaboutcircuits.com/showthread.php?t=24028

And here is his blog with tons of good info:
http://forum.allaboutcircuits.com/blog.php?b=190

 

From your description this might be closer to what you're after, though the output will need some drivers. The frequency and duty cycle are totally independent, and each control is stable.