On-chip sine-wave noise generator for analog IP noise tolerance measurements

A sine-wave noise generator with a harmonic-eliminated waveform is proposed for measuring the noise tolerance of analog IPs. In the waveform, harmonics up to the thirteenth harmonic are eliminated by combining seven rectangular waves with 22.5-degree spacing phases. This waveform includes only high-region frequency harmonic components which are easily suppressed by a low-order filter. In the circuit, the harmonic-eliminated waveform generator is combined with a current-controlled oscillator and a frequency-adjustment circuit. The sine-wave noise generator can generate power-line noise from 20 MHz to 220 MHz in 1 MHz steps. A spurious-free dynamic range (SFDR) of 45 dB is obtained at the 100 MHz noise frequency.