The Laser Diode Driver (LDD) is an important part in optical communication system; it acts as an interface between the data source and the optical source (Laser). The design of this circuit using CMOS technology which has low conductivity (gm), (less than from bipolar technology), is a challenge for designers especially at high data rate (>1 GB/s) because LDD must provide high current swing to obtain large optical output power.
In this research a simulation software using Personal Simulation Program with IC Emphasis PSPICE (2006) is used to study the performance of the LDD circuit using (0.18µmCMOS technology) at (1 GB/s), the peak to peak jitter is (110ps). In addition analyzing an automatic power control circuit, so that when changing the temperature from (0 – 80˚C) the Laser current changing is (5mA), and an improvement of reference voltage circuit has been added, since a constant voltage (319mV) achieved when the power supply voltage changes from (2.15-6V).

Keywords: Laser Diode Driver , pre-driver , Extinction Ratio.