A Radiation-Hardened 15–22-GHz Frequency Synthesizer in 22-nm FinFET
David Dolt, Samuel Palermo
Abstract
High-speed radiation-hardened frequency synthesizers are a key block in spaceborne communications systems. This article presents a 15–22-GHz radiation-hardened phase-locked loop (PLL) designed in a 22-nm FinFET process with hardening techniques for single-event upset (SEU) and total ionizing dose (TID) implemented in all key PLL blocks. Electrical performance tradeoffs arising from the radiation-hardening techniques are discussed and experimentally verified. The PLL achieves a figure of merit (FoM) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 240.89 dB at 15 GHz with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 64-dBc spur levels. Moreover, heavy-ion testing performed at the Texas A&M Cyclotron Institute, College Station, TX, USA, validated the PLL’s resilience to SEU across a linear energy transfer (LET) range from 10 to 70 MeV <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\cdot$</tex-math> </inline-formula> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /mg, while TID testing performed at the Texas A&M TRIGA reactor up to 300 krad confirmed the PLL’s robustness to total dose effects.