Title :
Design of a fast digital double relaxation oscillation SQUID
Author :
Podt, M. ; Mieog, A.J. ; Flokstra, J. ; Rogalla, H.
Author_Institution :
Dept. of Appl. Phys., Twente Univ., Enschede, Netherlands
fDate :
3/1/2001 12:00:00 AM
Abstract :
A fast digital Double Relaxation Oscillation SQUID (DROS) with a relaxation oscillation frequency of 100 MHz has been developed. The digital DROS incorporates a DROS and a superconducting up-down counter that supplies the feedback flux. The major advantage of a DROS is that the relaxation oscillations generate an on-chip clock signal and therefore, no external clock is required. In order to maximize the slew rate without compromising the sensitivity, the quantization unit of the feedback flux was adapted to the flux noise of the DROS. This resulted in a designed flux slew rate of 5·106 Φ0/s. We will discuss the design optimization, numerical simulations, the layout and some experimental results of the digital DROS
Keywords :
SQUIDs; digital integrated circuits; digital readout; feedback oscillators; high-speed integrated circuits; integrated circuit layout; integrated circuit noise; nuclear electronics; relaxation oscillators; superconducting device noise; superconducting integrated circuits; cryogenic particle detector readout; design optimization; fast digital double relaxation oscillation SQUID design; feedback flux; flux noise; numerical simulations; on-chip clock signal; quantization unit; relaxation oscillation frequency; sensitivity; slew rate; superconducting up-down counter; Clocks; Counting circuits; Design optimization; Feedback; Frequency; Numerical simulation; Quantization; SQUIDs; Signal generators; Superconducting device noise;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
