16 Channel PWM Servo Driver
Moderators: adafruit_support_bill, adafruit

16 Channel PWM Servo Driver

by ajpollme on Mon Jan 28, 2013 11:10 am

I am trying to use the PWM function on this to run a few SSRs connected to heating elements for an all electric home brewing set up. The tutorial states that the PWM frequency will go to as low as 1hz, but when I try to set the frequency that low with an led hooked up for testing it is still running quite a bit faster than 1hz more like 10 to 20 hz (I don't have an oscilloscope to check it but it is noticeably flickering). So can I really set this to 1hz or is there a typo in the tutorial?
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Re: 16 Channel PWM Servo Driver

by adafruit_support_bill on Mon Jan 28, 2013 11:46 am

Hmmm. Looking at the chip specs, the upper limit in the documentation is almost certainly wrong. Not sure about the lower limit. I'll look into this...
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Re: 16 Channel PWM Servo Driver

by ktownsend on Mon Jan 28, 2013 12:12 pm

Sorry, this is a type in the tutorial. The actual range is 40-1000Hz based on a 25MHz internal clock. :(
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Re: 16 Channel PWM Servo Driver

by ajpollme on Mon Jan 28, 2013 1:53 pm

Thanks, I guess I will have to write code to run the slow PWM on the GPIO pins. I was just hoping to save myself some trouble and use a shortcut.
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