摘要
在D类音频功率放大器中,驱动死区时间控制是一个很流行的术语。它被用来防止击穿的发生。在当今的D类音频功率放大器的设计中,随着开关频率的不断提高,死区时间间隔相对于开关周期也变得足够的长,以至于影响了系统的性能。然而,短而有效的死区时间设置对于在D类转换端口获得更好的线性总是有益的。本文将详细阐述驱动死区时间控制对D类音频功率放大器的影响。通过采用内置的死区时间产生模块的驱动集成电路芯片来降低D类音频功率放大器外部端口器件的数量。仅通过两个额外的电阻来设置DT引脚电压就很容易地得到可选择的预编程死区时间。这种设置死区时间的方式可以阻止外部噪声对系统转换时间的影响,这对于音频的性能是至关重要的。
Driver deadtime control is a popular scheme used to prevent the occurrence of the shoot-through issue in a Class-D APA （ audio power amplifier ）. As the switching frequency is continually increasing in today＇ s APA design, the deadtime interval is now long enough relative to the switching period to impact the system performance. However, a shorter effective deadtime setting is always beneficial to achieve better linearity in a Class-D switching stage. In this paper, the influence of driver deadtime on the Class-D APA is investigated in detail. Using a driver IC included an internal deadtime generation module reduce the number of external components in the output stage of a Class-D audio amplifier. Seleetable deadtime programmed through the DT-pin voltage is an easy and reliable function, which requires only two external resistors. This seleetable way of setting deadtime prevents outside noise from modulating the switching timing, which is critical to the audio performances.
出处
《中国集成电路》
2008年第12期30-35,共6页
China lntegrated Circuit
