针对激光扫描仪接收系统对信号窄脉宽、高重频、大带宽的设计要求, 提出 2种保持时间可调的峰值保持电路的设计方法。一种利用跨导型放大电路实现峰值保持, 单稳态触发器实现保持时间控制; 一种利用 FastFET运算放大器和与门延时实现保持时间可控的峰值保持电路。通过软件仿真对 2种设计方法进行对比分析, 选择更适合激光扫描仪接收系统的跨导型峰值保持电路。经实验验证, 该电路可对 15 ns脉宽、 200 kHz重频和 50 MHz带宽的信号有效保持, 且保持时间可调。

The receiving system of laser scanner requires the signal with narrow pulse, high repetition rate and wide bandwidth. To meet these requirements, two peak-holding circuits whose holding time is adjustable are proposed. For one method, transconductance amplifier circuit is adopted to realize the peak-holding, and mono-stable multivibrator is applied for holding time control. For the other method, by combining FastFET calculation amplifier with AND gate delay, the peak-holding circuit with controllable holding time is implemented. After simulation and analysis, transconductance amplifier circuit is selected. Experiments show that the selected circuit can hold the peak of the signal with 15 ns pulse width, 200 kHz repetition rate and 50 MHz bandwidth, and the holding time is adjustable.