A low voltage differential signaling (LVDS) receiver includes a receiver circuit including first and second inputs coupled to first and second conductive pads, respectively, and an output coupled to an input of a digital controller, and a dummy transmitter circuit including a first input coupled to receive a common mode voltage (VCM) tune signal, a second input coupled to a loopback input signal, a third input coupled to a loopback enable signal, a first output coupled to the first input of the receiver circuit, and a second output coupled to the second input of the receiver circuit. When a test mode of operation is enabled, the digital controller asserts the loopback enable signal, and the dummy transmitter circuit generates a pair of test differential signals based on the VCM tune signal, wherein the VCM tune signal varies to test the LVDS receiver over a range of common mode voltages.

A low voltage differential signaling (LVDS) receiver includes a receiver circuit including first and second inputs coupled to first and second conductive pads, respectively, and an output coupled to an input of a digital controller, and a dummy transmitter circuit including a first input coupled to receive a common mode voltage (VCM) tune signal, a second input coupled to a loopback input signal, a third input coupled to a loopback enable signal, a first output coupled to the first input of the receiver circuit, and a second output coupled to the second input of the receiver circuit. When a test mode of operation is enabled, the digital controller asserts the loopback enable signal, and the dummy transmitter circuit generates a pair of test differential signals based on the VCM tune signal, wherein the VCM tune signal varies to test the LVDS receiver over a range of common mode voltages.

An amplifier circuitry, may include a plurality of differential pair amplifiers connected to differential input connections and differential output connections, and a common mode return current connection connected to the each differential pair amplifier of the plurality of differential pair amplifiers, wherein the common mode return current connection includes an insulation layer between a first portion of the common mode return current connection and a second portion of the common mode return current connection for common-mode stability.