FAQ | Mar 08,2023
An op-amp is designed to be an amplifier with very high gain and input impedance. The input impedance of an op-amp is typically in the order of millions of ohms, which means that it draws very little current from the signal source.
If a sensor is connected directly to an op-amp, the op-amp may draw a small amount of current from the sensor, which can affect the sensor’s output voltage. This can result in inaccurate readings or even damage to the sensor.
To avoid this problem, it is recommended to use a buffer amplifier between the sensor and the op-amp. The buffer amplifier has a high input impedance, which means it draws very little current from the sensor. This ensures that the sensor’s output voltage remains unaffected and the readings are accurate.
In summary, while an op-amp is an excellent amplifier, it is not designed to draw current from a sensor. It is best to use a buffer amplifier to ensure accurate readings and avoid any potential damage to the sensor.
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