2011 Volume E94.C Issue 6 Pages 1024-1031
A single tone pseudo-noise generator with a harmonic-eliminated waveform is proposed for measuring noise tolerance of analog IPs. In the waveform, the harmonics up to the thirteenth are eliminated by combining seven rectangular waves with 22.5- degree spacing phases. The proposed waveform includes only high region frequency harmonic components, which are easily suppressed by a low-order filter. This characteristic enables simple circuit implementation for a sine wave generator. In the circuit, the harmonic eliminated waveform generator is combined with a current controlled oscillator and a frequency adjustment circuit. The single tone pseudo-noise generator can generate power line noise from 20MHz to 220MHz with 1MHz steps. The SFDR of 40dB is obtained at the noise frequency of 100MHz. The circuit enables the measurement of frequency response characteristics measurements such as PSRR.
