
For standard instrumentation amplifier, a three op-amps instrumentation amplifier circuit is common, but if you need smaller component count and lower cost, you can use just two op-amps for the same function: a high impedance and good CMRR for sensor pre-amplification and buffering. Here is the circuit’s schematic duiagram: A two-op-amp instrumentation amplifier [...]
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Using LMV721/722 or any other high impedance op-amps, you can build an instrumentation amplifier using standard three op-amps instrumentation amplifier circuit. The figure below shows the circuit’s schematic diagram. The final stage of this instrumentation amplifier is a differential-input, differential-output amplifier, with two voltage followers feed its inputs. These two voltage followers assure [...]
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Current amplifier application need very low input bias current, and CA3140 is one of suitable op-amps for this purpose. The circuit’s schematic diagram is shown in the figure below. In the circuit, low current is supplied at the input potential as the power supply to load resistor RL. When the load current is [...]
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This is Operational an Amplifier (Op-Amp) Oscillator circuit. This circuit has some advantages, they are this circuit can be operated at low frequencies with relatively small capacitors, it has a completely-symmetrical output waveform along with a buffered output and it will always self start and cannot hang up because there is less dc positive feedback [...]
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Although this circuit use more resistor components than in basic standard three op-amps instrumentation amplifier circuit, this circuit has the benefit of easy gain adjustment with only one control resistor. Because the easy gain adjustment feature, this circuit topology has been used inside a single chip instrumentation amplifier ic. The figure below shows the schematic [...]
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Operational amplifiers for tone control circuit application require high slew rate, wide bandwidth, high input impedance, and high output current characteristics, and CA3140 is suitable for this purpose. Look at the following tone control circuit’s schematic diagram for the design. The tone control circuit in the figure above use a very popular Baxandall [...]
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