Lead-on detection circuitry of biopotential acquisition system

A lead-on detection circuitry of a biopotential acquisition system, comprising:

• an input terminal;
• a duty-cycle controller, configured to generate a first clock signal;
• a transmitting signal generator, configured to generate a transmitting signal to the input terminal according to the first clock signal;
• a mixer-based receiver, configured to perform a mixing operation based on the first clock signal and the transmitting signal to generate an output signal, wherein the output signal indicates if an electrode of the biopotential acquisition system is in contact with a human body, and the electrode is coupled to the input terminal;
• wherein the duty-cycle controller further generates a second clock signal, wherein a frequency of the second clock signal is lower than a frequency of the first clock signal;
• and the mixer-based receiver is enabled or disabled based on the second clock signal.

A lead-on detection circuitry of a biopotential acquisition system, comprising:

• an input terminal;
• a duty-cycle controller, configured to generate a first clock signal;
• a transmitting signal generator, configured to generate a transmitting signal to the input terminal according to the first clock signal;
• a mixer-based receiver, configured to perform a mixing operation based on the first clock signal and the transmitting signal to generate an output signal, wherein the output signal indicates if an electrode of the biopotential acquisition system is in contact with a human body, and the electrode is coupled to the input terminal;
• wherein the duty-cycle controller comprises:
• an oscillator, wherein the oscillator is configured to generate the first clock signal and a second clock signal, and a frequency of the second clock signal is lower than a frequency of the first clock signal;
• and
• a reference signal generator, configured to generate a reference signal to the transmitting signal generator or the mixer-based receiver;
• wherein the reference signal generator is enabled or disabled based on the second clock signal.