0-5v pwm converter problem

[nikhilt007]

hai
here i made 0-5 pwm converter to 0-10
i gave my 0-5v pwm i/p to an non inverting op-amp circuit (uc741)
it is working but the problem is that when i am given 0v i/p op-amp out giving 3.5v

i cant able to nullify output offset voltage

please help me


8-O

 

[betwixt]

741s are not a good choice of op-amp but you will have to show your schematic to get an exact answer.

Brian.

 

[goldsmith]

hai
here i made 0-5 pwm converter to 0-10
i gave my 0-5v pwm i/p to an non inverting op-amp circuit (uc741)
it is working but the problem is that when i am given 0v i/p op-amp out giving 3.5v

i cant able to nullify output offset voltage

please help me

Hi as Brian mentioned before , 741 is not a good choice for this aim . can you show us your schematic please ? then we can help you more .
But i think you'd better try with LF356 or every better op amps !
Best Wishes
Goldsmith

 

[crutschow]

If you have a 5V supply, then 3.5V is the typical maximum output from a 741. To get 5V you need a rail-rail type op amp.

 

[nikhilt007]

somebody sugest me a circuit for pwm 0-5v to 0-10v

 

[gehan_s]

hi,


I think you can use something like this. I have put some arbitrary resistor values.

 

[goldsmith]

somebody sugest me a circuit for pwm 0-5v to 0-10v

Hi
I think you'd better to mention a thing exactly ! what do you mean by "for PWM 0-5 to 0-10 v " ?? is your mean you're looking for a PWM signal which has variable amplitude ? if so may i ask you what is application of such a waveform ? if you mention these parameters exactly , then i can help you in a correct path .
Best Wishes
Goldsmith

 

[nikhilt007]

thanks for all of your suggestion but i achieved it
by defferent methode

 

[alexan_e]

It is great that you found the solution yourself but you could at least share the solution with the rest of the members

 

[nikhilt007]

It is great that you found the solution yourself but you could at least share the solution with the rest of the members

i have done it by using just only one optocoupler mct6
i given the 0-5v pwm input to mct6 and just apply to rc parellel circuit
and i am getting the result
actually mct6 contyain transistor and iam amplified my signal using npn transistor inside the mct6


for getting correct 0-10v out put make periode of your pwm as larger and increase duty cycle from minimum very slightly you will get a 0-10v varying output
and applide it across parellel rc circuit