| 摘要 |
A high-output high-voltage output digital amplifier the gain of which can be easily adjusted while maintaining the high accuracy and low distortion. The digital amplifier is a combination of a ternary output DELTA SIGMA modulator and a PWM amplifier and provides gain adjusting means while maintaining high accuracy and low distortion. The digital amplifier comprises (A) a DELTA SIGMA modulator (11) supplied with an input signal and a synchronizing signal, (B) a PWM modulating circuit (14) supplied with a gain control input signal and the synchronizing signal and adapted to control the duty cycle, (C) a logical circuit (17) supplied with signals from the DELTA SIGMA modulator and PWM modulating circuit and adapted to perform a logical operation thereof, and (D) a pulse amplifier (15) supplied with signals from the logical circuit and adapted to output states as the difference between the two outputs.
|
