Radiation Hardened Analog-to-Digital Convertor with Automatic Offset Voltage Compensation

Abstract

Radiation hardened ADC with automatic offset voltage compensation was developed. TID radiation effect in the ADC was investigated at different temperatures. The designed ADC devices demonstrate high radiation hardness. Up to total dose level 100 krad(Si) any significant radiation induced drift didn't observed in transfer characteristics of all irradiated devices. It is achieved by using techniques such as application of automatic offset voltage compensation circuit together with enclosed layout transistors (ELT), located in ADC control logic. Also, edge-less n-channel MOSFETs with additional guard rings were used to increase the radiation hardness of digital interface and control logic of ADC. In contrast with control logic ELT not used in interface logic. Thus significant degradation of digital interface power supply current was observed unlike control logic power supply. Developed device can be considered as a good technical decision for self-diagnostic systems of electronic devices proposed for application under ionizing radiation impact, especially for systems of spacecrafts and satellites.