| 摘要 |
A pulse width modulation digital to analog converter includes a pulse generator, a combiner and a filter. The pulse generator receives an n-bit digital word, partitions the input digital word into a plurality of sub-words, and produces a plurality of periodic pulse width modulated waveforms, each waveform's duty cycle and amplitude being representative of one of the plurality of sub-words. Since the sub-words have unique magnitude significance relative to the n-bit input word and relative to the other sub-words, each of the plurality of pulse width modulated waveforms are weighted according to the corresponding sub-word significance. The combiner receives the plurality of weighted pulse width modulated waveforms and combines them into a composite pulse width modulated waveform. The filter receives the composite periodic pulse width modulated waveform and produces an output parameter such as voltage, which corresponds to the time average of the composite waveform, where the output parameter is a function of the composite waveform's duty cycle and amplitude.
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