數(shù)字示波器功能強(qiáng)大,使用方便,但是價(jià)格相對(duì)昂貴。本文以Ti的MSP430F5529為主控器,以Altera公司的EP2C5T144C8 FPGA器件為邏輯控制部件設(shè)計(jì)數(shù)字示波器。模擬信號(hào)經(jīng)程控放大、整形電路后形成方波信號(hào)送至FPGA測頻,根據(jù)頻率值選擇采用片上及片外高速AD分段采樣。FPGA控制片外AD采樣并將數(shù)據(jù)輸入到FIFO模塊中緩存,由單片機(jī)進(jìn)行頻譜分析。測試表明:簡易示波器可以實(shí)現(xiàn)自動(dòng)選檔、多采樣率采樣、高精度測頻及頻譜分析等功能。Digital oscilloscope is powerful and easy to use, but also expensive. The research group designed a low-cost digital oscilloscope, the chip of MSP430F5529 of TI is chosen as the main controller and the device of EP2C5T144C8 of Altera company is used as the logic control unit. Analog signal enter the programmable amplifier circuit, shaping circuit and other pre-processing circuit. The shaped rectangular wave signal is sent to FPGA for measure the frequency. According to the frequency value to select AD on-chip or off-chip high-speed AD for sampling. FPGA controls the off-chip AD sampling and buffers AD data by FIFO module. The single chip microcomputer receives the data, and do FFT for spectrum analysis. The test shows that the simple oscilloscope can realize automatic gain selection, sampling at different sampling rates, high precision frequency measurement and spectrum analysis.
