本文選題：反激變換器　切入點(diǎn)：同步整流　出處：《西安科技大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：隨著電子技術(shù)的發(fā)展,芯片的供電電壓越來越低,但目前供電電源的輸出部分通常采用二極管整流,由于其正向?qū)▔航递^大,降低了電源效率,而采用通態(tài)電阻小的功率MOS管代替二極管實(shí)現(xiàn)整流,可以避免這一問題。反激變換器因其結(jié)構(gòu)簡(jiǎn)單,成本低廉,在小功率領(lǐng)域得到廣泛應(yīng)用,因此,對(duì)反激變換器輸出同步整流驅(qū)動(dòng)控制芯片進(jìn)行研究具有理論研究意義及工程應(yīng)用價(jià)值。通過對(duì)反激變換器和同步整流技術(shù)工作原理及工作波形進(jìn)行分析,提出了反激變換器輸出同步整流驅(qū)動(dòng)芯片設(shè)計(jì)方案。通過對(duì)輸出同步整流MOS管的漏源電壓進(jìn)行采樣,在同步整流MOS管漏源電壓小于零時(shí),原邊開關(guān)管關(guān)斷,開通同步整流MOS管;通過對(duì)流過同步整流MOS管電流進(jìn)行采樣放大,流過其電流小于關(guān)斷閾值時(shí),關(guān)斷輸出同步整流MOS管。通過在驅(qū)動(dòng)芯片內(nèi)置輔助電源,簡(jiǎn)化驅(qū)動(dòng)芯片外圍電路。輔助電源主要由電容充電模塊和LDO模塊組成,原邊開關(guān)管導(dǎo)通電容充電模塊儲(chǔ)能,LDO模塊為芯片低壓控制電路提供穩(wěn)定的輸出電壓;通過對(duì)帶隙基準(zhǔn)源原理的研究,設(shè)計(jì)了一個(gè)無運(yùn)放的低溫度系數(shù)帶隙基準(zhǔn)電壓源,其溫度系數(shù)為10.42ppm/℃。最后完成了一款反激變換器輸出同步整流驅(qū)動(dòng)芯片的設(shè)計(jì),基于0.35um5V/60VBCD仿真庫(kù)文件,采用Cadence工具對(duì)芯片內(nèi)部關(guān)鍵電路模塊進(jìn)行了仿真和驗(yàn)證。采用所設(shè)計(jì)的驅(qū)動(dòng)控制芯片搭建反激變換器系統(tǒng)仿真平臺(tái),對(duì)系統(tǒng)進(jìn)行了仿真,仿真結(jié)果驗(yàn)證了所設(shè)計(jì)芯片的可行性�；�0.35um 5V/60V BCD設(shè)計(jì)規(guī)則文件,采用Cadence軟件完成了整體電路版圖設(shè)計(jì),并通過了 DRC檢查驗(yàn)證。
[Abstract]:With the development of electronic technology, the supply voltage of the chip becomes lower and lower. However, diode rectifier is usually used in the output part of the power supply at present. This problem can be avoided by using a power MOS transistor with low on-state resistance instead of the diode. Flyback converter is widely used in the field of low power because of its simple structure and low cost. The research on the output synchronous rectifier drive control chip of flyback converter has theoretical significance and engineering application value. The working principle and working waveform of flyback converter and synchronous rectifier technology are analyzed. The design scheme of output synchronous rectifier drive chip of flyback converter is presented. By sampling the leakage voltage of output synchronous rectifier MOS transistor, when the leakage voltage of synchronous rectifier MOS tube is less than 00:00, the primary side switch tube is turned off and the synchronous rectifier MOS tube is turned on. By sampling and amplifying the current of the synchronous rectifier MOS tube, the output synchronous rectifier MOS tube is turned off when the current is less than the turn-off threshold. The auxiliary power supply is mainly composed of capacitor charging module and LDO module. By studying the principle of bandgap reference source, a low temperature coefficient band-gap voltage reference without operational amplifier is designed. The temperature coefficient is 10.42 ppm / 鈩，

本文編號(hào)：1607219