A multiple quantum well ridge waveguide laser at 1.5-mu-m wavelength and a driver circuit comprised of four heterojunction bipolar transistors (HBT's) have been monolithically integrated on a semi-insulating InP substrate. This optoelectronic integrated circuit (OEIC) has been realized by metalorganic vapor phase epitaxy. The laser threshold current is near 20 mA. The HBT dc current gain is 40 and the unity gain cutoff frequency is 30 GHz. Pseudorandom pulsed operation of the OEIC transmitter has been demonstrated for bit rates up to 5 Gb/s. This is, to our knowledge, the highest bit rate that has been reported for HBT-based OEIC transmitters.