A low-power CMOS digitally synthesized 0-13 MHz agile sinewave generator

A low-power monolithic 1 /spl mu/m CMOS IC generates a 26 MHz-wide single-sideband, frequency-hopped spread-spectrum waveform for wireless transmission in the 902-928 MHz unlicensed ISM band. A direct digital frequency synthesizer (DDFS) on this IC produces 10b samples of sine and cosine waveforms whose frequency is selected with an 11b input word, followed by an on-chip 10b D/A converter (DAC) to convert the DDFS output into a sampled-data analog signal. Simplifications in architecture and circuits reduce dissipation of this 2.9/spl times/4.9 mm/sup 2/ IC to 40 mW at 40 MHz with 3 V supply.<>