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The presented laser/modulator driver for optical communication aims at low power dissipation. The single-ended output with a push-pull driver allows a 3.3 V supply while leaving 1.8 V for the laser. The laser is DC coupled to the open collector output stage so that the DC bias current of the driver is used for biasing of the laser. The minimum supply voltage of the IC is 2.7 V. The circuit was realised in the Philips QUBiC4 BiCMOS IC process with a cut off frequency fT of 37GHz. The chip was mounted as a die on board and the electrical output signal was measured. The signal-to-noise ratio is 7.44dB, the measured bit error rate is <10-12. The minimal rise/fall time is about 42 ps and the measured rms jitter is 5.3 ps. The active area of the IC is 800×700 μm2. The dissipation is 240 mW for a supply voltage of 3.3 V and room temperature.