Systems and methods for input leakage reduction and linearity improvement in signal processing systems

An apparatus comprising:

• an input terminal configured to receive an input signal;
• a first circuit coupled to the input terminal, the first circuit comprising:
• a first transistor coupled to the input terminal;
• and
• a level-shifter coupled to the first transistor and configured to provide a first bias voltage to the first transistor;
• a second circuit coupled to the first circuit, the second circuit comprising a second transistor, the second transistor comprising a base terminal coupled to a first supply voltage;
• a first switch coupled to the input terminal and a ground potential, the first switch being configured to establish a first conduction path between the input terminal and the ground potential in response to a first control signal;
• an amplifier comprising a first input and an output, the amplifier being configured to generate an output signal by amplifying the input signal;
• and
• an output terminal coupled to the output of the amplifier, the output terminal being configured to provide the output signal.

An apparatus comprising:

• an input terminal configured to receive an input signal;
• a first circuit coupled to the input terminal, the first circuit comprising a first transistor coupled to the input terminal and a first node, the first circuit is configured to conduct a transient current between the input terminal and the first node in response to a voltage transient event;
• a second circuit coupled to the first circuit, the second circuit comprising a second transistor, the second transistor comprising a base terminal coupled to a first supply voltage;
• a first switch coupled to the input terminal and a ground potential, the first switch being configured to establish a first conduction path between the input terminal and the ground potential in response to a first control signal;
• an amplifier comprising a first input and an output, the amplifier being configured to generate an output signal by amplifying the input signal;
• a second switch coupled to the input terminal and the first input of the amplifier;
• and
• an output terminal coupled to the output of the amplifier, the output terminal being configured to provide the output signal.