An analog multi-tone signal generator for built-in-self-test applications

This paper presents the design of an analog oscillator capable of generating multi-tone signals by encoding the information in an oversampled delta-sigma modulated bit-stream. With the exception of an imprecise lowpass filter, the proposed design is completely digital allowing accurate control of the amplitude, frequency, and phase of all sinusoids making up the multi-tone signal. Simulations and FPGA experiments performed to date have verified the performance of the proposed design which is envisioned to open new directions in the mixed analog/digital testing field