| 摘要 |
PROBLEM TO BE SOLVED: To easily obtain a multichannel PWM digital/analog converter which is low-cost and has high performance by constructing a converter, such that the rise of the PWM signal of each channel can be shifted from one another, corresponding to an offset value. SOLUTION: Adders 802 to 804 on and after a CH2 with a 1st channel (CH1) performing zero detection as reference are provided, and a phase difference component to the CH1 is added to the value of each data bus as an offset value and respectively latched to latching circuits 102 and 104. The offset value of each channel is defined as a value, that is mutually different so as to be shifted byαeach among all channels, so that none of the phases of PWM output waveforms overlap. Also, on and after the CH2, each offset detection circuit is used instead of a zero detection circuit 30 of the CH1. The offset detection circuit outputs an Hi level signal, when the counter value of a counter 20 becomes an offset value. The offset value is equivalent to the offset value added by an adder.
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