7-DECADE TUNING RANGE CMOS OTA-C SINUSOIDAL VCO

A new operational transconductance amplifier-capacitor (OTA-C) based s inusoidal voltage-controlled oscillator (VCO) das been designed and fa bricated, the oscillation frequency of which can be tuned from 74mHz t o 1MHz. The VCO uses a new OTA whose transconductance is adjusted by u sing a set of special current mirrors. These current mirrors operate i n weak inversion and their gain can be controlled continuously through a gate voltage over many decades. This is the first report of such a wide tuning range for CMOS sinusoidal oscillators. Experimental result s are provided.