#The Fifth Lichuang Electronic Design Competition#0-12MHZ adjustable signal source

* 1. Self/team introduction, geek hobby, communication major * 2. Briefly introduce the project based on STC8A8K64S4A12, AD9833 signal generator, convenient for experiments * 3 Describe the project details. Use MCU to write to AD9833 to generate waveforms, LC filtering, opa690 amplifies. A sliding rheostat changes the amplification ratio. Make the waveform amplitude adjustable and improve the load capacity* 4. Describe the challenges faced by the project and the problems solved. The signal bandwidth is high and the noise is high. * 5. Describe the key points involved in the hardware and software parts of the project. Main control: STC8A8K64S4A12: For instructions, see the attachment. dds chip: ad9833 writing: see ad833 attachment description. Filtering: lc passive low-pass filter design: Designed using Filter Solutions. The tutorial can be found in the attachment! [lc.png]            Signal amplification: For the selection of opa690, see the attachment description. * 6. Project material list display tools: soldering iron, oscilloscope, Lichuang EDA, ![image.png] * 5. Upload project pictures 5.1. Print the competition logo picture on the PCB![3D] ![Wiring] ![Lichuang 5 yuan for proofing] 5.2. Other pictures of the project![EDA.png] ![Things diagram] ![Power on work] ![250khz square wave] ![2khz square wave] ![63khz sine wave] ![2khz sine wave ] Wave] ![Triangular Wave] * 6. Demonstrate your project and record it as a video for upload 6.1, Video Upload Contest official website 6.2, B station video title and link: https://www.bilibili.com/video/BV1qt4y1i7ua/ * 7. Whether it is publicly released for the first time 7.1. Whether the project has been published or won an award before, please indicate the first publication* 8. See the attachment for open source documents* 9. References [https://blog.csdn.net/lmf666/article/details/107140845 ](https://blog.csdn.net/lmf666/article/details/107140845) [https://blog.csdn.net/xiaokai1999/article/details/107170376](https://blog.csdn.net/ xiaokai1999/article/details/107170376) [https://www.cnblogs.com/chulin/p/8616069.html](https://www.cnblogs.com/chulin/p/8616069.html)