Hi everyone,
I'm designing a circuit to measure the current from a mini-solar panel (0.5 W) which normally reaches 80-100 mA. My circuit is attached to this post.
I have a Gain of 6 with the resistors R2=5k and R1=1k because G=1+(R2/R1). Normally the input voltage on op-amp (LM324) is 0.2-0.4 V and always the output voltage is under 3.7-3.8 V. I don't understand why this happens. If 0.3 V is the input voltage and with gain of 6, the output voltage would be 1.8 V (0.3*6=1.8).
The power supply of op-amp is the +5V and GND from Arduino.
Can you help me with this ?
I'm designing a circuit to measure the current from a mini-solar panel (0.5 W) which normally reaches 80-100 mA. My circuit is attached to this post.
I have a Gain of 6 with the resistors R2=5k and R1=1k because G=1+(R2/R1). Normally the input voltage on op-amp (LM324) is 0.2-0.4 V and always the output voltage is under 3.7-3.8 V. I don't understand why this happens. If 0.3 V is the input voltage and with gain of 6, the output voltage would be 1.8 V (0.3*6=1.8).
The power supply of op-amp is the +5V and GND from Arduino.
Can you help me with this ?
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