Noise sensor

A noise sensor having a first power terminal and a second power terminal and a third power terminal for receiving signals from a power supply, the noise sensor comprising:

• a noise separator having a first input, a second input, a third input, a first output for providing a first output signal representative of common mode noise and a second output for providing a second output signal representative of differential mode noise;
• and
• a noise sensing unit, wherein the noise sensing unit comprises:
• a first capacitive element that couples the first input of the noise separator to the first power terminal;
• and
• the noise sensing unit further comprises either:
• a second capacitive element that couples the second input of the noise separator to the second power terminal;
• a first resistive element that couples the first input of the noise separator to the third power terminal;
• and
• a second resistive element that couples the second input of the noise sensor to the third power terminal,
• or the noise sensing unit further comprises:
• a second capacitive element that couples the second input of the noise separator to the third power terminal;
• a coupling between the second power terminal and the third input of the noise separator;
• a first resistive element that couples the first input of the noise separator to the second power terminal;
• and
• a second resistive element that couples the second input of the noise separator to the third power terminal via the second capacitive element;
• wherein the noise separator includes circuitry that is configured to:
• generate the first output signal representative of common mode noise by adding a signal from the first input to a signal from the second input, and
• generate the second output signal representative of the differential mode noise by taking a difference of the first and second input signals.