一種基于單片機的數控開關電源設計

摘要：基于單片機的數控開關電源是利用單片機實現對開關電源的輸出電壓設定、輸出電壓步進調整、輸出電壓和輸出電流顯示等數字控制。本文設計的數控開關電源由兩部分組成。開關電源部分采用基于PWM控制的不對稱半橋功率變換器，由模擬控制芯片KA3525產生PWM信號經驅動電路實現對功率變換電路的輸出電壓控制，實現電壓的穩定輸出。數控部分采用凌陽單片機的D/A輸出對KA3525的誤差比較器的參考端進行數字給定，實現對輸出電壓的設定、步進調整和顯示等功能。文中給出了系統設計框圖，對各部分電路進行了分析，并給出了必要的實驗波形，經測試證實設計方法是可行的。將成熟的單片機技術與現有的開關電源技術進行簡單結合實現數控，值得借鑒。 敘詞：數控開關電源 不對稱半橋功率變換器 凌陽單片機 KA3525 Abstract：Digital control switching power supply is the use of single chip microcomputer implementation of the switching power supply output voltage settings, adjust the output voltage step, the output voltage and output current shows such as digital control. In this paper, switching power supply design of NC is composed of two parts. Switching power supply based on the PWM control part of the asymmetrical half-bridge power converter, using KA3525 generate PWM, the use of drive circuit implementation of the power conversion circuit output control. Digital control part of the D/A using Sunplus single chip microcomputer KA3525 error output of comparator reference side of the figure given, implementation of the output voltage settings, step adjust and display functions. Mature single-chip microcomputer technology with the existing switching power supply technology for easy implementation combined with digital control. Keyword：Digital control switching power supply, Asymmetrical half-bridge power converter, Sunplus single chip microcomputer, KA3525