一種基于單片機的數(shù)控開關(guān)電源設(shè)計

摘要：基于單片機的數(shù)控開關(guān)電源是利用單片機實現(xiàn)對開關(guān)電源的輸出電壓設(shè)定、輸出電壓步進調(diào)整、輸出電壓和輸出電流顯示等數(shù)字控制。本文設(shè)計的數(shù)控開關(guān)電源由兩部分組成。開關(guān)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(chǎn)生PWM信號經(jīng)驅(qū)動電路實現(xiàn)對功率變換電路的輸出電壓控制，實現(xiàn)電壓的穩(wěn)定輸出。數(shù)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(shù)字給定，實現(xiàn)對輸出電壓的設(shè)定、步進調(diào)整和顯示等功能。文中給出了系統(tǒng)設(shè)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(jīng)測試證實設(shè)計方法是可行的。將成熟的單片機技術(shù)與現(xiàn)有的開關(guān)電源技術(shù)進行簡單結(jié)合實現(xiàn)數(shù)控，值得借鑒。 敘詞：數(shù)控開關(guān)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