A 3.5-Gb/s burst-mode laser driver with automatic power control (APC) fabricated in 0.25 /spl mu/m 1P5M CMOS process is presented. With the proposed waveform shaping circuit, the driver could operate under a single 3.3 V power supply without sacrificing output headroom, and it could output 6 mA to 60 mA modulation current with negligible overshoot. Measurements on mounted chips show clear electrical eye diagrams operating over 3.5-Gb/s data rate with typical rise/fall times (20% to 80%) of 84/97 ps. Moreover, an optical eye diagram is also demonstrated by connecting the driver to a 1.25-Gb/s 1310 nm laser diode. The laser turn on/off time is about 30/20 ns, much less than the criterion (512 ns) that the IEEE 802.3ah standard has proposed.