Abstract
The designed D class amplification has characterized of improver full PWM program high efficiency and lower filter requirements. CPLD realization of adopted full-bridge PWM improvement program, and combined with the realization by DSP SERDES, digital interpolation and noise shaping processing, etc., can be realized by high-fidelity audio amplifier. Digital power amplifier designed for digital audio output to the audio signal directly to amplification, digital sound and power was amplified to provide a complete integrated solution. It has been improved PWM program, the output pipe by using high-speed switching MOSFET tubes, are connected into a complementary symmetric H-bridge structure, the average efficiency of around 85% can be achieved by the combination of 1:1 two-change single-output circuits, noise and interference by shielding methods, in addition to short-circuit protected output. Its working principle is: the input signal with the triangular wave signal is compared by comparing the device after a pulsed signal to the preamp circuit, and then, after filtering low-pass filter to ensure that the output .signal within a certain bandwidth. Class D amplifiers can achieve this because of efficiency, because the D-type switch-mode power amplifier with the work, which is similar or the output MOSFET is fully activated (saturated), or is completely closed (cut off) of the. Transistors can be reduced and thus the power loss and increase efficiency by amplifier.
Key Words: D class power amplification；Programs to improve the PWM ；pulse-width modulation；current overload protection；
