Title :
An eighth-order CMOS low-pass filter with 30-120 MHz tuning range and programmable boost
Author :
Bollati, Giacomino ; Marchese, Stefano ; Demicheli, Marco ; Castello, Rinaldo
Author_Institution :
STMicroelectronics, Cornaredo, Italy
fDate :
7/1/2001 12:00:00 AM
Abstract :
A CMOS low-pass filter with programmable boost is presented. The architecture is a Gm/C type with the Gm value controlled through a resistor servo approach. The transfer function has been optimized in order to reduce the sensitivity to component parameter variations. The 1:4 tuning range is achieved by exploiting a dual-loop control over a degenerated differential pair. At the nominal output voltage swing of 200 mVpp differential, a THD better than 40 dB is guaranteed. The high-frequency boost is programmable between 6 and 14 dB. This filter, realized as a cascade of biquad and first-order cells, is implemented in a 0.25-μm 2.5-V CMOS technology. It dissipates 120 mW with fc=120 MHz and has a die area of 0.23 mm2
Keywords :
CMOS analogue integrated circuits; biquadratic filters; cascade networks; circuit tuning; continuous time filters; low-pass filters; programmable filters; transfer functions; 120 mW; 2.5 V; 30 to 120 MHz; CMOS implementation; Gm/C type architecture; HDD equalisation; biquad and first-order cells cascade; degenerated differential pair; dual-loop control; eighth-order CMOS low-pass filter; high-frequency boost; linear phase filters; optimised transfer function; programmable boost; resistor servo approach; transconductors; tuning range; CMOS technology; Circuits; Digital filters; Dynamic range; Low pass filters; Nonlinear filters; Resistors; Transconductors; Transfer functions; Voltage;
Journal_Title :
Solid-State Circuits, IEEE Journal of
