A device comprising: a first terminal to receive a first common-mode reference voltage, Vcm; a second terminal to receive a second common-mode reference voltage, Vcm ADC; a variable gain amplifier comprising an input terminal to receive an input signal, an output terminal to provide a first output signal, V P, that is biased based on the first common-mode reference voltage, Vcm, and a supply voltage terminal to receive a first supply voltage; a voltage shifter circuit comprising a first input terminal coupled to the output terminal of the variable gain amplifier, a second input terminal, and an output terminal to provide a second output signal, Vinp, that is biased based on the second common-mode reference voltage; a variable gain amplifier half replica module comprising an output terminal coupled to the second input terminal of the voltage shifter circuit, the variable gain amplifier half replica module operable to control the second output signal of the voltage shifter circuit based on the first common-mode reference voltage and the second common-mode reference voltage; an analog to digital converter comprising an input terminal coupled to the output terminal of the voltage shifter circuit, the analog to digital converter configured to provide a digital output signal based on the second output signal; wherein the voltage shifter circuit comprises: a resistor having a first terminal coupled to the output terminal of the variable gain amplifier, and a second terminal coupled to the input terminal of the analog to digital converter; and a first transistor comprising a first current electrode terminal coupled to the second terminal of the resistor, a second current electrode terminal coupled to a voltage reference, and a control terminal coupled to the output terminal of the variable gain amplifier half replica module, wherein the first transistor is variably active in a linear mode to cause a voltage at the first current electrode terminal to be biased by the second common-mode reference voltage in response to a voltage provided by the variable gain amplifier half replica module. a first terminal to receive a first common-mode reference voltage, Vcm; a second terminal to receive a second common-mode reference voltage, Vcm ADC; a variable gain amplifier comprising an input terminal to receive an input signal, an output terminal to provide a first output signal, V P, that is biased based on the first common-mode reference voltage, Vcm, and a supply voltage terminal to receive a first supply voltage; a voltage shifter circuit comprising a first input terminal coupled to the output terminal of the variable gain amplifier, a second input terminal, and an output terminal to provide a second output signal, Vinp, that is biased based on the second common-mode reference voltage; a variable gain amplifier half replica module comprising an output terminal coupled to the second input terminal of the voltage shifter circuit, the variable gain amplifier half replica module operable to control the second output signal of the voltage shifter circuit based on the first common-mode reference voltage and the second common-mode reference voltage; an analog to digital converter comprising an input terminal coupled to the output terminal of the voltage shifter circuit, the analog to digital converter configured to provide a digital output signal based on the second output signal; wherein the voltage shifter circuit comprises: a resistor having a first terminal coupled to the output terminal of the variable gain amplifier, and a second terminal coupled to the input terminal of the analog to digital converter; and a first transistor comprising a first current electrode terminal coupled to the second terminal of the resistor, a second current electrode terminal coupled to a voltage reference, and a control terminal coupled to the output terminal of the variable gain amplifier half replica module, wherein the first transistor is variably active in a linear mode to cause a voltage at the first current electrode terminal to be biased by the second common-mode reference voltage in response to a voltage provided by the variable gain amplifier half replica module. a resistor having a first terminal coupled to the output terminal of the variable gain amplifier, and a second terminal coupled to the input terminal of the analog to digital converter; and a first transistor comprising a first current electrode terminal coupled to the second terminal of the resistor, a second current electrode terminal coupled to a voltage reference, and a control terminal coupled to the output terminal of the variable gain amplifier half replica module, wherein the first transistor is variably active in a linear mode to cause a voltage at the first current electrode terminal to be biased by the second common-mode reference voltage in response to a voltage provided by the variable gain amplifier half replica module.