Precise opamp gain (POG) design allows high-frequency SC filters using high-bandwidth op amps with low but precisely-known dc-gain, whose value is used as a parameter in the capacitor sizing. Using an op amp dc-gain Ao with a maximum relative deviation /spl epsi/, this concept allows the same performance accuracy obtained with standard design using an opamp with dc gain Ao//spl epsi/. In this work, using a standard 0.5/spl mu/m CMOS technology and 5V supply, 150MSample/s is achieved, consuming 20mW. The CMOS opamp dc-gain is set with a closed-loop gain-control circuit. In addition, the output dc-voltage is fixed by a CMOS circuit. This results in dc output voltage independent of technological variations, enabling rail-to-rail output swing.
Severi, F., Baschirotto, A., Castello, R. (1999). A 200MSamplels 10mW Switched-Capacitor Filter in 0.5pm CMOS Technology. In Digest of Technical Papers - IEEE International Solid-State Circuits Conference (pp.398-483). Institute of Electrical and Electronics Engineers Inc. [10.1109/ISSCC.1999.759321].
A 200MSamplels 10mW Switched-Capacitor Filter in 0.5pm CMOS Technology
Baschirotto, A;
1999
Abstract
Precise opamp gain (POG) design allows high-frequency SC filters using high-bandwidth op amps with low but precisely-known dc-gain, whose value is used as a parameter in the capacitor sizing. Using an op amp dc-gain Ao with a maximum relative deviation /spl epsi/, this concept allows the same performance accuracy obtained with standard design using an opamp with dc gain Ao//spl epsi/. In this work, using a standard 0.5/spl mu/m CMOS technology and 5V supply, 150MSample/s is achieved, consuming 20mW. The CMOS opamp dc-gain is set with a closed-loop gain-control circuit. In addition, the output dc-voltage is fixed by a CMOS circuit. This results in dc output voltage independent of technological variations, enabling rail-to-rail output swing.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


