Radiation-hardening technique for supply-regulated LC-tank voltage controlled oscillator

The power supply of LC-tank voltage-controlled oscillators (VCOs) demonstrates high sensitivity to single-event transients (SETs). This study presents a novel radiation-hardening-by-design (RHBD) technique that can automatically detect and mitigate SET disturbances. The proposed method incorporates additional floating well contacts to monitor fluctuations in well potential induced by heavy-ion strikes, serving as trigger signals for the RHBD circuitry. Operational amplifier (AMP) within low dropout regulator (LDO) circuit serve as an example to demonstrate the effectiveness of the proposed hardening technique for SET mitigation. Simulation results confirm the radiation tolerance of the RHBD LDO-VCO system operating at 27.35 GHz, using 28 nm bulk CMOS process. With proper configuration, the LDO-VCO can achieve complete immunity when subjected to heavy-ion impacts on sensitive nodes within AMP devices. This technique demonstrates broad applicability in the radiation-hardened design of analog integrated circuits for space applications.