開(kāi)關(guān)電源基礎(chǔ)培訓(xùn)資料

1、開(kāi)關(guān)電源基礎(chǔ)培訓(xùn)資料開(kāi)關(guān)電源基礎(chǔ)培訓(xùn)資料供電電源單片機(jī)顯示、鍵盤(pán)外圍芯片其他存儲(chǔ)AD語(yǔ)音。其余需要供電的電路一、線(xiàn)性電源和開(kāi)關(guān)電源一、線(xiàn)性電源和開(kāi)關(guān)電源ACIn？VDC1VDC2實(shí)現(xiàn)方法：實(shí)現(xiàn)方法：1、線(xiàn)性電源、線(xiàn)性電源 2、開(kāi)關(guān)電源、開(kāi)關(guān)電源1、線(xiàn)性電源、線(xiàn)性電源RDZCFVinI R1 I O R1R2I B Q1RL V O -V Z V BE1 I in I CE I RZ I RI RZ Q)()1(121BEZoVVRRV %100%100inoininooVVIVIV 0 0.5 1 V o 50% EFFICIENCY / V in 100% Virtually all pow

2、er is dissipated in pass transistor QQdissinoooinoPV IV IPPExample 1VVin12 VVo5 VVVVoin7 %7.41%100125 Example 2VVin12 VVo10 VVVVoin2 %3.83%1001210 VO SERIES REGCFRLCin mains 50-60 Hz Requires bulky 50-60 Hz transformer large size excessive weight 優(yōu)點(diǎn)優(yōu)點(diǎn) 輸出電壓噪聲小輸出電壓噪聲小 動(dòng)態(tài)響應(yīng)快動(dòng)態(tài)響應(yīng)快結(jié)構(gòu)簡(jiǎn)單結(jié)構(gòu)簡(jiǎn)單 適用于小功率適用于小功率 缺

3、點(diǎn)缺點(diǎn) 低效率低效率 無(wú)隔離無(wú)隔離- 超重超重- 超大超大V CEQ I CV CE I CQQV CEQ V CE t I CI CQt CQCEQQcondQdissIVPP 線(xiàn)性電源中Q的工作狀態(tài)switchingtransitions I CV CE on QQoffVCE sat turn-off transition turn-ontransition t t Qoffon T off T on QV CE I CI CQonVCE sat V CEQoff swcondoffonQoffQondissPPPPPPP regulatorlinear of P VIVIPQcondC

4、EQoffCQoffsat,CECQoncondsoffCEoffCQonsonCEOoffCQonswfTVIfTVIP 6161soffonCEQoffCQonfTTVI)(61 開(kāi)關(guān)電源！二、典型開(kāi)關(guān)電源主電路拓?fù)涠?、典型開(kāi)關(guān)電源主電路拓?fù)?、非隔離：BUCK，BOOST，BUCK/BOOST2、隔離：flyback，forward，bridge type。inputswitching network averaging network output DCFVinI o RL i in i DvD o V v S +-v L +-SLFi LVinI o i in i L V o +-

5、T onVinT off V o +- I o i L i D BUCK converterD min D max 01 M = D M= V O V in M min =V O V in max Mmax V O V in min =D 連續(xù)模式VinI o i in S V o +-i S INPUT FILTERBUCK CONVERTER0LINCINLFCFD增加輸入濾波器V cc V out 0D 1V GS 02D D 1V F C B+-V GS V out PWMdriverD max 50% B 2C1:1V out VC2+VC1+V cc V out 0D 1V GS

6、0D 2D 1average VGSmust be zero (same areas)MOSFET 的驅(qū)動(dòng)的驅(qū)動(dòng)BUCK電路特點(diǎn)電路特點(diǎn) 輸出電壓小于輸入電壓輸出電壓小于輸入電壓 輸入輸出無(wú)隔離輸入輸出無(wú)隔離 輸入電流脈動(dòng)大輸入電流脈動(dòng)大 高端驅(qū)動(dòng)高端驅(qū)動(dòng)BOOST converterVinI o Lv +- v D+- L Fi S i L V o +- i D S v S +- C F i inR L D T on V o +-ViniinIOV o +-VinT offiinIOMD111DDVVMino BOOST電路特點(diǎn)電路特點(diǎn)輸出電壓比輸入電壓高輸出電壓比輸入電壓高輸入輸出無(wú)隔離輸

7、入輸出無(wú)隔離輸入電流脈動(dòng)小輸入電流脈動(dòng)小直接驅(qū)動(dòng)直接驅(qū)動(dòng)啟動(dòng)需要另加電路啟動(dòng)需要另加電路VinI o i L V o +- v D+- i D S +- C F i inL Fv LR L D V o +-V in T on iiniOV o Vin +-T off iOiLBUCK/BOOST converterBUCK REGIOND0.5MD1DDDDVVMino 隔離式開(kāi)關(guān)電源主電路主要講flyback反激=buck/boost+變壓器DVPvQiQiO QCFnViniSvOVST S QONQOFFiOiSvQiQVin+nVOQ 能量在開(kāi)關(guān)關(guān)斷時(shí)傳輸?shù)礁边吥芰吭陂_(kāi)關(guān)關(guān)斷時(shí)傳輸?shù)礁?/p>

8、邊 變壓器必須儲(chǔ)存能量（開(kāi)關(guān)開(kāi)通時(shí)），必須開(kāi)氣隙變壓器必須儲(chǔ)存能量（開(kāi)關(guān)開(kāi)通時(shí)），必須開(kāi)氣隙 無(wú)變壓器復(fù)位問(wèn)題無(wú)變壓器復(fù)位問(wèn)題T S QONQOFFiOiSvQiQVin+nVOQQ-OFFVINVQ LMiMVSiS=niMQ-OFFiQn RL VO CF=nVOLMdiMdtIOVO Q-ONVINVPVQ LMiMVSiS= 0Q-ONiQiP=0n RL CF=VINLMiMdiMdtIO1、開(kāi)關(guān)Q開(kāi)通2、開(kāi)關(guān)電流（原邊電流）線(xiàn)性上升3、輸出二極管截止4、開(kāi)關(guān)兩端電壓為零T S QONQOFFiOiSvQiQVin+nVOQQ-OFFVINVQ LMiMVSiS=niMQ-OFFiQ

9、n RL VO CF=nVOLMdiMdtIOVO Q-ONVINVPVQ LMiMVSiS= 0Q-ONiQiP=0n RL CF=VINLMiMdiMdtIO1、開(kāi)關(guān)Q關(guān)斷2、開(kāi)關(guān)電流為零3、輸出二極管導(dǎo)通，副邊電流線(xiàn)性下降4、開(kāi)關(guān)兩端電壓DVPvQiQiO QCFnVINiSvOVST S QONQOFFiOiSvQiQVin+nVOVinDCMQif COSSof Q is not zero工作在DCM狀態(tài)（這種情況多）T S QONQOFFiOiSvQiQVin+nVOVinDCMQif COSSof Q is not zero第三個(gè)狀態(tài)Q-OFFVINVQ LMiMVSiS=niM

10、Q-OFFiQn RL VO CF=nVOLMdiMdtIOVINVQ LMiM=0iS=0Q-OFFiP=0n RL VO CFiP=0IOD-OFF DCMQ-ONVINVPVQ LMiMVSiS=0Q-ONiQiP=0n RL VO CF=VINLMiMdiMdtIO反激電路特點(diǎn)反激電路特點(diǎn)從從Buck/boost電路變換過(guò)來(lái)電路變換過(guò)來(lái) 能量在開(kāi)關(guān)關(guān)斷時(shí)傳輸能量在開(kāi)關(guān)關(guān)斷時(shí)傳輸不需要額外的能量復(fù)位電路不需要額外的能量復(fù)位電路變壓器為了儲(chǔ)存能量，必須加氣隙變壓器為了儲(chǔ)存能量，必須加氣隙在小功率場(chǎng)合非常流行，特別適合于多路輸出在小功率場(chǎng)合非常流行，特別適合于多路輸出三、單片開(kāi)關(guān)電源三、單片開(kāi)關(guān)電源五、五、TINYSwitch-介紹介紹TINYSwitch將PWM控制器與功率開(kāi)關(guān)MOSFET合二為一封裝在一起，已成為開(kāi)關(guān)電源IC發(fā)展主流。采用單片開(kāi)關(guān)集成電路設(shè)計(jì)開(kāi)關(guān)電源，可簡(jiǎn)化電路、進(jìn)一步縮小體積、降低成本。 電壓檢測(cè)管腳(L)：輸入電壓的欠壓和過(guò)壓檢測(cè)