Has anyone with a good scope ever taken a look at the actual signal a tiny15 or tiny85 outputs when it's running 'flat out' in PWM mode at it's highest frequency? A tiny15 has a 25.6mhz clock, and the tiny85's is supposed to go up to 64mhz which means they should be able to output 12.8/32mhz PWM signals on the PWM line respectivly, I've heard rough estimates that the rise/fall times on the I/O lines are about 8ns so this is going to end up producing anything but a 50% duty cycle square wave. Does anyone have either of these chips around and want to check it? If anyone has the time to do so could they also list how the line was checked? Specifically the scopes input capacitance/resistance and any other possible stray capacitance/inductance in the test circuit?
Joined: Mon. Aug 4, 2003
Posts: 860 View posts