METHOD AND APPARATUS FOR GENERATING AN ANALOGUE SIGNAL FROM AN ENCODED DIGITAL SIGNAL

摘要

A digital audio signal generator (30) includes an EPROM memory (32) containing a digitally encoded audio signal sampled at a fixed rate. An address counter (48) retrieves the digital values sequentially from the memory, and the data is fed to a segment generator which generates a segment of a predetermined wavefuction. The audio signal is generated by joining together consecutive segments. The segment generator includes output DACs (66, 70) and reference DACs (60, 62) which control the output amplitudes of the output DACs. A summing amplifier (72) combines the outputs from the output DACs to produce the output audio signal. A counter (44) generates a sequence of values representing a straight line wave function, which values are fed to the output DACs.