- Joined Jan 9, 2019
exactly, an unusual circuit!That is an unusual circuit. I can not make any comment on its function because there is not enough information.
What is the square symbol in the bottom left of the diagram connected to? Is it the capacitive sensor ?
What load is connected to the output?
What is the frequency of the PWM signal?
Is the PWM signal +10V referenced to ground (which is not shown)?
PWM10V Lets say this is a 10V square wave.the square is the capacitive touch spring
Thank you very much for your help ...very much appreciated.Using a 10khz PWM signal. Running 10X faster will allow you to measure smaller capacitors. Running at 1/10 the frequency is for measuring much larger capacitors.
1pF of touch capacitance "C2" =1.58 volts out. (10khz 50% duty cycle)
10pF = 1.7V
100pF = 2.13V
1000pF = 6.83V
View attachment 219943
I think "PWM signal" is just a source of a clock. Some computers have many PWM and no/little clocks.What is the purpose of the the PWM signal? If the circuit is a capacitive touch sensor, all you need is a fixed frequency square wave.
Exactly! The toy processors need everything added on "shilds" so that the "sketches" can do something useful. And a PWM wave would allow the output voltage to be adjusted to some specific level with no touch..I think "PWM signal" is just a source of a clock. Some computers have many PWM and no/little clocks.
But then we don't really know anything on this project.
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