M. Ingels et al., A CMOS 18-THZ-OMEGA 240-MB S TRANSIMPEDANCE AMPLIFIER AND 155-MB/S LED-DRIVER FOR LOW-COST OPTICAL-FIBER LINKS/, IEEE journal of solid-state circuits, 29(12), 1994, pp. 1552-1559
The realization of a complete low cost CMOS optical fiber link using a
LED and PIN as optical components is presented, The driver and receiv
er are realized in a standard 0.8 mu m digital CMOS process which make
s integration with a DSP possible. The driver is a current steering tr
ansistor combined with a small quiescent current source, The modulatio
n current is 60 mA which allows a 155 Mb/s optical data-rate, The rece
iver is a three-stage transimpedance amplifier followed by a signal co
nverter which provides digital output signal levels. The three-stage c
onfiguration makes possible the realization of a high transimpedance (
150 k Omega), necessary to obtain a high sensitivity, combined with a
high bandwidth. The achieved optical data-rate is 240 Mb/s for 1 mu A
input modulation currents, This results in a transimpedance bandwidth
of 18 THz Omega, which is one order of magnitude higher than recently
published circuits, The speed performance of the total link is limited
by the optical time-constant of the LED, leading to a 155 Mb/s optica
l link, designed for use in four-fiber interboard connections in 622 M
b/s B-ISDN systems.