This paper presents a reconstructive oscillator based sinusoidal signal generator which can produce both high and low frequency signals by switching the oscillator into different mode. In addition, analog and digital signals can be produced concurrently in both modes. Also, signal amplitude and oscillation frequency can be precisely controlled compared with pure analog signal generator. Except for a 1-bit D/A converter and analog filter, the circuits are entirely constructed by digital circuits. One can trade the digital hardware complexity to moderate the difficulties in designing the analog reconstructive filter. The generated high and low frequency signals are suitable to serve as the test stimuli in built-in self test methodology for A/D converters to extract the transmission and static parameters, respectively.