Hello,
I'm working on a voltage equalizer for supercapcitor stacks for my final year project, and for that goal, I need to be able to measure voltage from each supercaps.
I'm trying the differential amplifier using opamp lm358. Schematic attached. The problem I faced is the choice of resistance value. Obviously I need high input impedance, so the resistor wouldn't bleed too much of energy from supercaps. However, as I increases the resistance value, the output voltage drops significantly. What I want is for the output voltage level to be the same as the differential inputs voltage level.
Could anyone tell me how to fix this problem? The solution might be something different from my attachment as long as it fit my requirement. All help is appreciated.
I'm working on a voltage equalizer for supercapcitor stacks for my final year project, and for that goal, I need to be able to measure voltage from each supercaps.
I'm trying the differential amplifier using opamp lm358. Schematic attached. The problem I faced is the choice of resistance value. Obviously I need high input impedance, so the resistor wouldn't bleed too much of energy from supercaps. However, as I increases the resistance value, the output voltage drops significantly. What I want is for the output voltage level to be the same as the differential inputs voltage level.
Could anyone tell me how to fix this problem? The solution might be something different from my attachment as long as it fit my requirement. All help is appreciated.
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