高速A/D芯片输入信号的调理电路

A Modulation Circuit for the Input Signal of High-speed A/D chip

腔衰荡光谱DSP处理系统中,衰荡信号的数字化需要用高速A/D来实现。目前,高速A/D芯片对输入信号的幅值范围有着严格的要求,为保证输入腔衰荡光谱DSP处理系统中A/D芯片的信号满足其要求,并实现其性能最优化,文章设计了一套以峰值探测器、可变增益放大器、高速运放及C8051单片机为核心器件的高速A/D芯片输入信号调理电路。实验结果表明:该电路满足设计要求,同时,该电路还可用于其它需要对电振幅进行调理的场合。

In a cavity ring-down DSP modulation system, a high-speed A/D is needed to digitalize the ringdown signal. Presently, high-speed A/D chip has strict requirement on the amplitude of the input signal. In order to meet the restriction, and optimize the capability of the system, a modulation circuit for the input signal of high-speed A/D chip is designed and its performance is tested in this message. The circuit consists of a peak detector, a variable gain amplifier, a high-speed amplifier and a C8051 SCM. The result of the test shows that this circuit satisfies the initial purpose of the design. Meanwhile, this circuit can be used in other occasions that need to modulate the amplitude of the signal.