OP90 Single-Supply Current Monitor

This is Single-Supply Current Monitor circuit. Amplifying the voltage drop across a resistor placed in a series with the current to be measured is the essential of current monitoring. However it is difficult because with low precision op amps this greatly limits the overall resolution and only small voltage drops can be tolerated. Here is the schematic diagram of Single-Supply […]

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INA159 Dual-Polarity, Bidirectional Current-Shunt-Monitor Circuit

This is a INA159 Dual-Polarity, Bidirectional Current-Shunt-Monitor Circuit. This circuit uses OPA340 because it has near rail-to-rail input and output swing ranges that allow the output voltage of the circut to approach 0 and 5V. The gain of OPA340 is set to +100 and the INA159 gain is +0.2V/V. This circuit has gain of +20V/V. Here is the circuit : […]

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Self Powered Current Sensing

This is a current sensing circuit that senses the current at the high side (between load and positive supply). This circuit     take advantage from Rail-to-Rail input of the LT1494 and the microampere supply current. Here is the circuit : At the op-amp, the output is connected directly to the inverting input that will keep the inverting input is equal to […]

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High DC Voltage Current Sensing

LTC6101 op-amp can be used to build High voltage current monitoring/sensing. This circuit can senses current in 500 volts system. Here is the schematic diagram of the circuit: To hold off the voltage, two external Mosfets is added to the circuit. It will allow to connect LTC6101 to very high potentials and measure the current flow.  At Rsense, the output […]

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