Title :
Managing subthreshold leakage in charge-based analog circuits with low-VTH transistors by analog T- switch (AT-switch) and super cut-off CMOS (SCCMOS)
Author :
Ishida, Koichi ; Kanda, Kouichi ; Tamtrakarn, Atit ; Kawaguchi, Hiroshi ; Sakurai, Takayasu
Author_Institution :
Center for Collaborative Res., Univ. of Tokyo, Japan
fDate :
4/1/2006 12:00:00 AM
Abstract :
The analog T-switch (AT-switch) scheme is introduced to suppress subthreshold-leakage problems in charge-based analog circuits such as switched capacitors and sample-and-hold circuits. A 0.5-V sigma-delta modulator is manufactured in a 0.15-μm FD-SOI process with low VTH of 0.1 V using the concept. The scheme is compared with another leakage-suppression scheme based on super cut-off CMOS (SCCMOS) and the conventional circuit which are also fabricated. The sigma-delta modulator based on AT-switch greatly improves 8.1-dB SNDR through reducing nonlinear leakage effects while the modulator based on SCCMOS improves the dynamic range rather than the SNDR by comparing with the conventional sigma-delta modulator.
Keywords :
CMOS analogue integrated circuits; analogue circuits; leakage currents; sigma-delta modulation; silicon-on-insulator; 0.1 V; 0.15 micron; 0.5 V; AT-switch; FD-SOI process; SCCMOS; analog T-switch; charge-based analog circuits; leakage-suppression scheme; low threshold voltage transistors; nonlinear leakage effects; sigma-delta modulator; subthreshold leakage; subthreshold-leakage problems; super cut-off CMOS; Analog circuits; CMOS analog integrated circuits; Delta-sigma modulation; Digital circuits; Manufacturing processes; Subthreshold current; Switched capacitor circuits; Switches; Switching circuits; Voltage; FD-SOI; Low; sigma-delta modulator; subthreshold leakage; switched capacitor;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2006.870761
