| 摘要 |
PURPOSE:To realize the power amplifier to be applied to highly broad band, by partly delaying the pulse width modulation signal by 1/2 period of the carrier signal frequency, power-amplifying them with two output amplifiers, adding the outputs and reducing the noise level. CONSTITUTION:When the input signal is zero, the output of the pulse width modulator 2 is input to an amplifier 4. Further, the pulse output delayed by 1/2 period is input to the amplifier 4'. The output of the amplifiers 4, 4' is inverted by 1/2 period, i.e. 180 deg., at duty 50%, for the phase. By adding the outputs through a coil L for the low-pass filter, the current flowing to a capacitor C for integration is cancelled to cancel the ripple components completely. Further, when the input signal is positive, the ripple components are doubled for the frequency of the respective ripple components. |
