LVDS Transmitter for Cold-Spare Systems in High Flux Environments

A high-bandwidth LVDS Transmitter (TX) has been proposed for redundant parallel connection of semiconductor devices in cold-spare systems. The cold-spare configuration is widely adopted for secure system operation of artificial satellite exposed to highly-radiated environment. For applying to the configuration in radiation hardened application, the LVDS-TX has i) off-chip driver consisting of only NMOS transistors to enhance latch-up immunity, ii) replica biasing for common mode voltage stabilization independently to off-chip loading, iii) multiple guard ring between large NMOS and N-Well areas. The proposed LVDS-TX has been fabricated by using bulk I/O and SOI core transistors in a 65 nm FDSOI process. Measurement results show over-500Mbit/sec stable data communication, and remarkable suppression of BER (Bit Error Rate) degradation compared to commercial device under ${}^{84}\text{Kr}^{17+}$ exposure of 322.0 MeV at flux of over 5x105 count/cm2/s.