摘要 |
A pulse width modulated signal amplifier includes a power source, an integrator supplied with an input signal to be pulse-width-modulated and a carrier signal from a carrier signal oscillator, a comparator connected to the output of the integrator for producing a pulse width modulated signal, an output amplifier supplied with a DC voltage from the power source, and a negative feedback circuit connected between the input of the integrator and the output of the output amplifier. The negative feedback circuit becomes effective after a predetermined time from the time when the power source becomes ON so as to avoid the oscillation of the closed loop including the integrator.
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