Title :
A low-distortion BiCMOS 7th-order Bessel filter operating at 2.5 V supply
Author :
Yang, F. ; Enz, C.C.
Author_Institution :
Electron. Lab., Swiss Federal Inst. of Technol., Lausanne, Switzerland
Abstract :
This paper presents the design of a 7th-order continuous-time Bessel filter using a new low-voltage and highly-linear BiCMOS OTA. A high-gain and parasitic-insensitive integrator is obtained by using an active capacitor scheme. The filter has been fabricated in a 1 μm, double-poly 6-GHz BiCMOS process. The filter is operated at 2.5 V supply and has a nominal -3 dB cut-off frequency set at 600 kHz. The inband group delay variation is less than 10 ns. The THD measured with a 100 kHz input signal is less than -49 dB for a 2 Vpp amplitude. The filter can be frequency tuned with an external resistor over almost a decade with a gain variation less than 0.2 dB. The dynamic range is about 77 dB. A CMRR of 53 dB in the passband is observed, thanks to a careful common-mode control strategy
Keywords :
BiCMOS analogue integrated circuits; continuous time filters; harmonic distortion; 1 micron; 2.5 V; 600 kHz; THD; active capacitor; common-mode rejection ratio; cut-off frequency; double-poly BiCMOS process; dynamic range; frequency tuning; high-gain parasitic-insensitive integrator; inband group delay; low-distortion 7th-order continuous-time Bessel filter; low-voltage highly-linear OTA; Analog circuits; BiCMOS integrated circuits; Capacitors; Delay; Digital filters; Dynamic range; Frequency; MOS devices; Transconductors; Voltage;
Conference_Titel :
Custom Integrated Circuits Conference, 1995., Proceedings of the IEEE 1995
Conference_Location :
Santa Clara, CA
Print_ISBN :
0-7803-2584-2
DOI :
10.1109/CICC.1995.518244
