Abstract: Radiations present in harsh environments can significantly affects the performance of the silicon devices. Therefore, these effects should be taken into account in the system design phase. In this paper is shown the design of two high-speed drivers for optical Mach Zehnder modulators (MZM). The two drivers are designed to address the effects of low and high Total Ionization Dose (TID) levels, in the standard 65 nm CMOS technology. The target bit rate of the two drivers is 10 Gbps. The heavy effects that TID has on p-mosfets make the CMOS logic usable only for low radiation levels. Therefore, for TID levels higher than 10 Mrad the Current Mode Logic (CML) is more suitable. The use of this approach for the High TID driver allows reducing the effects of silicon damages. On the other hand, the CMOS driver allow halves the consumption power using only the 5% of layout area compared to the CML driver.