i am not seeing a 1.2 rms voltage after the divider and before entering 1IN + . this happens when i plug the opamp in the circuit. while the opamp is not plugged in, the divider shows me the 1.2 rms voltageSo the input voltage is divided by 11 (R2/R3), then divided by 2 (R1/R5), then multiplied by 2 (R7/R6). Why would you expect it to be 1.2V rms?
thanks for reply. i said offset to describe the whole functionality of the circuit. i tried LT spice to verify the concept before implementing but it seems that it is a hardware issue. the problem happens when plugging the opamp in the circuit. other with i can see the division as it should be. the voltage source was from a transformer BV020 with 180 ohm on the outputhi Tarek,
This is what LTSpice shows for your circuit.
[ please check make sure I have read your circuit correctly].
When you say Offset, do you mean you want the Vout signal to swing above 0V .?
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yes, this is true. mu fault i am using the second type with has output of 13.5 so i should have 1.2 rems voltage on the output. the issue i want to ask about is why plunging the opamp in the circuitry cause the voltage to drop after the divider from 1.2 to 0.5hi T,
With that 10k/1k voltage divider you will get 9Vrms * (1/11) = 0.818Vrms and that is what LTS shows, not 1.2Vrms as you have posted.
So, if the Vin is 9Vrms , swinging +/-Vrms about 0V, what signal do you want at Vout.?
Could you post a photo of your OPA layout, we can then check for any errors.
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Hi,i want to ask about is why plunging the opamp in the circuitry cause the voltage to drop after the divider from 1.2 to 0.5
by Duane Benson
by Aaron Carman
by Aaron Carman