An integrated laser/modulator driver for high-speed optical fiber communication systems has been developed. The integrated circuit was fabricated in a 0.2um gate length AIGaAs/lnGaAs/GaAs pseudomosphin high eleetron mobility transistors (pHEMTs) technology with thin film resistors, metal-insulator-metal (MIM) capacitors and spiral induetors. Its large signal bandwidth is over 12 GHz. The eye diagrams were measured at bit rate up to 12Gb/s with an output voltage swing of 3.4 Vp-p at single end of output. With measured charaetaristies we estimate that the driver IC can operate at bit rate of higher than 24 Gb/s. The power consumption is less than 1.8W using a single supply voltage of-4.5V.