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Measuring Pulse width modulation PWM

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1.) PWM
(Pulse Width Modulation) A modulation technique that uses a digital circuit to create a variable analog signal. PWM is a simple concept: open and close a switch at uniform, repeatable intervals. Analog circuits that vary the voltage tend to drift, and it costs more to produce ones that do not than it does to make digital PWM circuits. In addition, control of almost everything today is already in the digital realm.
For example, PWM is widely used to control the speed of a DC motor and the brightness of a bulb, in which case the PWM circuit is used to open/close a power line. If the line were opened for 1ms and closed for 1ms, and this were continuously repeated, the target would receive an average of 50% of the voltage and run at half speed or half brightness. If the line were opened for 1ms and closed for 3ms, the target would receive an average of 25%.

2.) time constant
(t) Time required for a capacitor in an RC circuit to charge to 63% of the remaining potential across the circuit. Also time required for current to reach 63% of maximum value in an RL circuit. Time constant of an RC circuit is the product of R and C. Time constant of an RL circuit is equal to inductance divided by resistance. a definite length of time marked off by two instants rise time Time for the leading edge of a pulse to rise from 10% of its peak value to 90% of its peak value. fall time
Time it takes the falling edge of a pulse to go from 90% of peak voltage to 10% of peak voltage.

3.) pulse width
Time interval between the leading edge and trailing edge of a pulse at a point where the amplitude is 50% of the peak value.

4.) DC offset
The change in input voltage required to produce a zero output voltage when no signal is applied to an amplifier

5.) Rate of Change - ROC
The speed at which a variable changes over a specific period of time.

6.) ripple voltage
The small variations in Dc voltage that remain after filtering in a power supply.

7.) period
Time to complete one full cycle of a periodic or repeating waveform.
 
Ok i got the definitions but i still don't know how to measure this stuff
on the oscilloscope i need some examples or those oscilloscope formulas
to do this stuff. I have to apply it to waveform checking on the oscilloscope and know where to look at and to measure this stuff from the definition and list i have thats my main problem.
 
We have already shown you examples but you seem to be missing the link

I think the only real way that this can get settled is IF you post one of yr waveforms THEN we can work on it to show you some of these definitions
 
Best way is to use a time delay sweep scope, or long memory length Dig Storage scope.

You can expand second sweep line and dial across original waveform to achieve expanded view on a smaller time per division view.

A step by step procedure is going to be a bit dependent on your particular model scope.
 
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