|
vnwservice manual download site
Three, class-d power amplifiervnwservice manual download site
Described above shows that the main factor affecting the efficiency of amplifier is no signal at the current size, that formed the current DC power loss. When there are no signals, larger DC current loss the greater the lower the efficiency. For this reason, in order to improve work efficiency should be reduced, so that when there is no signal input, there is no direct loss. However, the signal conduction angle is smaller, the greater the distortion, harmonic components in the output signal increases, these two requirements are contradictory.vnwservice manual download site
If the edge of the input waveform is very steep, even reduced, effect on the conduction angle is very small, little distortion deterioration, and efficiency can be improved. Limit State is the input signal for rectangle waveform steep wave, the wave, no matter how bias changes, because the front and rear edge is vertical-takeoff, conducting State is not changed, so was born working class-d power amplifier in pulse operation.vnwservice manual download site
Class-d amplifiers operate in off status, no signal lost when no current breakover, no direct loss. In fact, as the turn-off time device does not already have a small leakage current, when the device is not fully short circuit, there is a certain amount of pressure drop, so there is less loss of DC, so the actual efficiency of 80%~90%, this is still an existing amplifier efficiency high.vnwservice manual download site
It is because of the high efficiency of class d amplifiers, low power dissipation power, generate less heat, and can greatly reduce the size of radiator, can easily reach hundreds of Watts of continuous output power. In addition, class d amplifier at high frequencies than audio frequencies more than 10 times the pulse, so the rectifier ripple on the power supply circuit has little effect.vnwservice manual download site
1. Circuitvnwservice manual download site
Class-d power amplifier to switch status, the basic structure is mainly composed of the modulator, class-d amp and low pass filter, as shown in Figure 7.
8 Home Previous 2 3 4 5 6 7 Next Last |