Title :
A 20 MHz 6th order BiCMOS programmable filter using parasitic-insensitive integrators
Author :
Laber, C.A. ; Gray, P.R.
Author_Institution :
Micro Linear Corp., San Jose, CA, USA
Abstract :
A fast parasitic-insensitive continuous-time filter that uses an active integrating-capacitor is described. The filter IC consists of a sixth-order Bessel lowpass and a second-order cosine-equalizer stage. It is made up of three biquads with lowpass and bandpass outputs. Both outputs of the last stage are available with matched group-delay characteristics. The corner frequency is digitally programmable through the digital serial interface to 64 values over a 4 to 1 range. Techniques for excess-phase nulling and Gm-setting independent of supply and temperature are described. This 20 MHz, 5 V equalizer has 0.24% of total harmonic distortion with 2 Vp-p signals and is built in 1.5 mu m/4 GHz BiCMOS.<>
Keywords :
BiCMOS integrated circuits; active filters; band-pass filters; linear integrated circuits; low-pass filters; 1.5 micron; 20 MHz; 5 V; BiCMOS programmable filter; active integrating-capacitor; bandpass outputs; biquads; continuous-time filter; corner frequency; digital serial interface; excess-phase nulling; matched group-delay characteristics; parasitic-insensitive integrators; second-order cosine-equalizer stage; sixth-order Bessel lowpass; total harmonic distortion; transconductance setting; Band pass filters; BiCMOS integrated circuits; Capacitance; Equalizers; Passive filters; Resistors; Temperature; Transconductance; Transconductors; Voltage;
Conference_Titel :
VLSI Circuits, 1992. Digest of Technical Papers., 1992 Symposium on
Conference_Location :
Seattle, WA, USA
Print_ISBN :
0-7803-0701-1
DOI :
10.1109/VLSIC.1992.229270
