A multi-channel optical transmitter generally includes a first light source configured to emit light of a first wavelength, a second light source configured to emit light of a second wavelength, a first modulator configured to modulate the light of the first wavelength, and a second modulator configured to modulate the light of the second wavelength. The first modulator has a first anode and a first cathode, and the second modulator has a second anode and a second cathode electrically isolated from the first anode and the first cathode. The modulators (and optionally the light sources) are on a common substrate. A method of transmitting optical signals generally includes modulating light emitted from a first light source using a first modulator, and modulating light emitted from a second light source using a second modulator, where the first modulator receives a first modulation signal, and the second modulator receives a second modulation signal electrically isolated from the first modulation signal.