Two high-speed optical front-ends with integrated photodiodes in standard 0.18 μm CMOS

Two optical front-ends implemented in a standard 0.18 μm CMOS technology are presented. They differ mainly in layout topology of the photodiode. The front-end with classical n-well diode achieves a bitrate of 300 Mbit/s. At an input power of -8 dBm, the BER is 2×10^-10. The front-end with differential n-well diode outperforms the classical n-well topology and reaches bitrates up to 500 Mbit/s. At this speed, an input power of -8 dBm is sufficient to have a BER of 3×10^-10. Both front-ends consume only 17 mW.