Quad Band Digitally Controlled Oscillator for WCDMA Transmitter in 90nm CMOS

We present the first published implementation and measurements of a fully integrated phase path for a 3G polar transmitter in deep sub micron CMOS. It includes a single quad band digitally controlled oscillator (DCO) providing modulation capability to handle the wide bandwidth of the WCDMA phase (frequency) data and a switched inverter divider. The complete chip, with integrated LDOs, consumes 20mA from a 1.4V supply while providing a PN of -157dBc/Hz at a 40MHz offset for a 2GHz output