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I have created a circuit could anyone plz tell me if this circuit is right!!?
- Thread starter Vikyath Rao
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A lousy old 741 opamp design is 48 years old and it was designed to use a 30V power supply that is +15V and -15V.
Your circuit has the tiny voltage of -0.35V connected to an input that the datasheet says must never be done.
Pin 7 must be a +15V supply voltage but yours is connected to ground by a 1k resistor.
Pin 4 must be -15V but yours is connected to ground by a 1k resistor.
Please learn about the basics of opamps then select a modern one to try.
Your circuit has the tiny voltage of -0.35V connected to an input that the datasheet says must never be done.
Pin 7 must be a +15V supply voltage but yours is connected to ground by a 1k resistor.
Pin 4 must be -15V but yours is connected to ground by a 1k resistor.
Please learn about the basics of opamps then select a modern one to try.
Why not. Power connections notwithstanding, the input and feedback look like an inverting amplifier with a gain of -13.
-0.35 in, +4.66 V out.
ak
Your schematic shows an opamp with no very important power supply. The input voltage must never go outside the power supply voltages and since your opamp is not powered then the 0.35V is wrong and will damage it.
If pin 7 is +15V and pin 4 is -15V then the opamp will work fine with an output of +4.67V.
Why do you have both power supply pins connected to ground through a 1k resistor?
If pin 7 is +15V and pin 4 is -15V then the opamp will work fine with an output of +4.67V.
Why do you have both power supply pins connected to ground through a 1k resistor?
Unlikely, since it's not even a diode drop above the 0V supply.
It is wrong, but not so wrong as to kill anything.
I believe the manufacturer who says in the datasheet that the absolute maximum input voltage must not exceed the supply voltage, they do not say less than a diode drop is OK. Maybe they have very low voltage Schottky diode clamps in there? This sentence has been edited.
Why wasn't the opamp powered?? It is not a generator.
Why wasn't the opamp powered?? It is not a generator.
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And 200uA through diode clamps will do what?
Who is limiting the current from the 0.35V solar cell to 200uA? The current might be high enough to zap a tiny Schottky diode if there is one at the input of the opamp.
The opamp input has a 75 ohm resistor, not a 1k resistor. If the input has a 0.15V Schottky clamp diode then the 0.35V into the 75 ohm resistor results in a current of (0.35V - 0.15V)/75 ohms= 2.7mA. But the current must return through the power supply pins that each have a 1k resistor to ground so the current will be much less.
But the question was, "Is this circuit right?" No it is not since the opamp is not powered.
But the question was, "Is this circuit right?" No it is not since the opamp is not powered.
davenn
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since the OP hasn't returned
we will close the thread, the original Q has been answered long ago
@Vikyath Rao ..... no your circuit wont work
do some redesigning and post again in a new thread
Dave
we will close the thread, the original Q has been answered long ago
@Vikyath Rao ..... no your circuit wont work
do some redesigning and post again in a new thread
Dave
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