Hi everyone,
I have been trying to solve this question (in the Attachment) about generating a PWM.
first i want to understand is this an oscillator circuit but we added (R with vin).
i think know how to analysis the oscillator but what is the difference when we include the vin and R , is it going to affetc the analysis quite alot,i mean there will be an inital voltage on capacitor?.
i am thinking is that at positive terminal e+=V0*(R2/R1+R2),and current start to flow from vo through R and capacitor to ground plus some inital voltage across capacitor,hence at inverting terminal start increas in voltage till a point when the inverting becomes larger than positive terminal, then the state will change over and then capacitor start discharging through the R and vo to zener diode.
in addition how we can design the value of R3.
Any suggestions and any hints would be much appreciated.
Thanks
Sam
I have been trying to solve this question (in the Attachment) about generating a PWM.
first i want to understand is this an oscillator circuit but we added (R with vin).
i think know how to analysis the oscillator but what is the difference when we include the vin and R , is it going to affetc the analysis quite alot,i mean there will be an inital voltage on capacitor?.
i am thinking is that at positive terminal e+=V0*(R2/R1+R2),and current start to flow from vo through R and capacitor to ground plus some inital voltage across capacitor,hence at inverting terminal start increas in voltage till a point when the inverting becomes larger than positive terminal, then the state will change over and then capacitor start discharging through the R and vo to zener diode.
in addition how we can design the value of R3.
Any suggestions and any hints would be much appreciated.
Thanks
Sam
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