A transmitter (TX) circuit harvesting power from a power supply of a receiver (RX) circuit is disclosed herein. The TX circuit for data transmission over a differential channel comprises a driver circuit coupled with the differential channel across a first pair of resistors. One terminal of each resistor of the first pair coupled together at a common mode voltage node. The differential channel is series terminated at the RX circuit by a second pair of resistors to a power supply node of the RX circuit. The driver circuit includes a differential pair and a current source drawing current from the power supply node of the RX circuit. A pre-driver circuit coupled with the driver circuit provides an output of the pre-driver circuit as an input to the driver circuit. At least the pre-driver circuit is powered from the common mode voltage node of the driver circuit.