A cryogenic DAC operating down to 4.2 K. (April 2016)

• Record Type: Journal Article
• Authors: Rahman, M.T.; Lehmann, T.
• Is Part Of: Cryogenics. Volume 75(2016)
• Page Start: 47
• Page End: 55
• Publication Date: 2016-04
• Subjects: Quantum bits -- Silicon-on-Sapphire -- CMOS -- Cryogenic DAC -- Current steering DAC; Low temperature engineering -- Periodicals; Low temperature research -- Periodicals; 536.56
• DOI: 10.1016/j.cryogenics.2016.02.003
• Languages: English
• ISSNs: 0011-2275

Abstract

Highlights: We design a cryogenic CMOS self-calibrated 10 bit current steering D/A converter. The DAC is fully functioning and retain its 10 bit linear monotonic behavior from 4.2 K to 300 K. The cryogenic DAC works with lower supply voltage compared to room temperature. Power supply rail induced systematic errors have less influence on the DAC's static behavior. The converter achieves 0.35LSB DNL and consumes 32.18 mW power. Abstract: This paper presents a 10 bit CMOS current steering digital to analog converter (DAC) that operates from room temperature to as low as 4.2 K. It works as the core part of a cryogenic Silicon quantum computer controller circuit producing rapid control gate voltage pulses for quantum bits (qubits) initialization. An improved analog calibration method with a unique unit current cell design is included in the D/A converter structure to overcome the extended cryogenic nonlinear and mismatch effects. The DAC retains its 10 bit linear monotonic behavior over the wide temperature range and it drives a 50 Ω load to 516 mV with a full scale rise time of 10 ns. The differential non-linearity (DNL) of the converter is 0.35LSB while its average power consumption is 32.18 mW from a 3 V power supply. The complete converter is fabricated using a commercial 0.5 μm 1 poly 3 metal Silicon on Sapphire (SOS) CMOS process.