文档介绍：目录
摘要: 1
关键词: 1
1 系统设计 1
1
方案论证与选择 1
主控芯片的选择与论证 1
信号放大部分的选择与论证 1
整形部分电路的选择与论证 2
A/D转换方案选择与论证 2
系统整体框图 2
2 系统硬件电路设计 3
主控电路部分 3
整形部分 3
放大部分 4
显示部分 5
3 系统软件设计 5
4 系统的测试和误差分析 6
6
系统软件调试 6
系统整体测试 6
系统测试仪器 6
系统测量和误差分析 7
数据测量与分析 7
误差分析 7
5 参考文献 8
附录 8
附录1 8
附录2 9
摘要:本设计以C8051F020单片机为核心控制芯片,由信号发生器输出被测信号,一路信号经过放大器后,再由单片机处理是否转换档位。然后由C8051自带的12位ADC测量电压最大值,经过单片机处理,算出峰峰值。另一路经过TLV3501进行整形后,由单片机测量此信号频率,当频率大于200kHz时,转换档位进行分频测量。当频率小于200kHz时,直接测量被测信号频率。然后由单片机控制LCD-12864显示出被测信号的频率、峰峰值和波形。
关键词:C8051F020 放大器整形分频 ADC
Abstract: The design with C8051F020 SCM as the core control chip, was first measured signal input to the signal generator circuit design by manual shift, adjust the measured signal measurement range so that more accurate measure of the measured signal frequency, when measured signal voltage range is 1 V to 10 V, as the OPA2228 voltage measurement range is the biggest V, so signal attenuation circuit would be passing, and then sent into MCU ADC measure of the measured signal voltage, and after TLV3501 is shaped by the relay for program, after treatment, when the frequency shift less than 200 KHz/s directly to the MCU is processing the final frequency, when frequency more than 200 KHz/s need through the CD4518 split frequency processing and then sent to the microcontroller get tested frequency of the signal, and then the single-puter control in LCD 1602 tested showed on the frequency of the signal and waveform.
Key word: C8051F020 plastic surgery to enlarge points frequency
1 系统设计

低频交流信号测量系统最后要测的是输入信号的频率和峰峰值,为了更精确的测量被测信号,首先将输入信号进行放大或衰减,然后送往单片机进行峰峰值的测量,另外频率的测量可以在放大后进行整形然后进行程控换挡,然后经单片机A/D转换处理通过液晶显示屏可以看到被测信号的频率和峰峰值。
方案论证与选择
主控芯片的选择与论证
方案一:使用普遍的AT系列单片机,优点是便宜,易于操作,但是处理速度慢。
方案二:采用C8051F020,C8051F020处理速度快,自带有12位ADC转换器,外部集成度高,抗干扰能力强,从而能够提高精度。
综合考虑选择方案二。
信号放大部分的选择与论证
方案一:采用TI公司芯片OPA2228,该系列芯片噪音低、宽带宽、精度高、转换速度快、失调电压小,放大倍数可任意调节。