Active Conditioning

What It Does

Conditioning circuits ensures that signals are properly prepared for further processing.

Examples:

• Improves the accuracy of the measurement.
• Reduces the noise in the signal.
• Makes the signal compatible with the next stage of processing.
• Safeguards the subsequent processing stage from potential damage.

Limit maximum

With transistors

A transistor can act as a switch. In this building block the transistor switches the prefered voltage output on or off.

• Main advantage is that the max output voltage can be set any arbitrary external voltage.
• The diode and resistor protect the transistor.
• This is a more complex setup (than the diode-resistor ), but benefits for also being a buffer.

Remove offset with high-pass filter

Offsets are not always wanted. Especially for audio signals. A simple high-pass RC-network can remove your offset. Because a DC offset as like a veeeery low frequency a high-pass filter will remove it while passing higher frequencies.

Remove negatives

Non-inverting half wave precision rectifier

• Notice no voltages below 0V.

Inverting half wave precision rectifier

• Notice that the negative input values are mirrored and kept. The rest is removed from the output.

Full wave precision rectifier

• Notice that the negative input values are mirrored and kept.
• This circuit outputs the combination of the above two.