Abstract: A high performance photodetector is integrated with a high performance modulator and a resistor on a single semiconductor substrate, all three sharing a common node. Voltage biases are applied to each of the diodes of the photodetector and modulator. As light is incident on the photodetector a current is generated which causes a voltage drop across the resistor. The voltage across the modulator then becomes the difference between its voltage bias and the voltage drop across the resistor. By properly selecting a resistor any desirable voltage swing is achieved without electrical amplifiers. Since the device is primarily optical and on a single semiconductor substrate, the device is independent of data rate, subject only to the inherent timing constant of the circuit.