升壓芯片及其轉(zhuǎn)換效率

1、透明屏接口用升壓芯片及其轉(zhuǎn)換效率研究:經(jīng)多方搜集適用的升壓芯片資源信息，已獲取LM2733、PT1305、KTC218、MP1541、CP2121、RT9284A等六個型號的樣片供測試對比，下面列出其初步測試情況。下表中的數(shù)據(jù)都是基于特制試驗(yàn)電路板的測試結(jié)果，該試驗(yàn)板全部采用適于手機(jī)應(yīng)用的元件，尺寸較 小，功率裕量也不大；測試儀表主要是普通數(shù)字萬用表，在某些情況下，雖然做了許多努力以便盡量獲得 正確的測量方法和步驟，但由于VCC/Ivcc/lvbat等三個參數(shù)只能依次進(jìn)行測量，并且串入電流表對升壓電路的工作狀態(tài)肯定會有影響一一有時甚至影響很嚴(yán)重導(dǎo)致無法測量（MP1541尤甚），所以不能保證每次

2、測量都絕對準(zhǔn)確，表中的記錄或計(jì)算值僅供參考。另外，還有新推薦的CP2121/MP1542DK尚未測試。為達(dá)到精確測量的目的，后期特別采用了Agilent66319電源單獨(dú)為升壓電路供電，而手機(jī)用鋰電池塊或其它電源另行供電，構(gòu)成測試電路如下圖。圖中V1、mA1為電源本身的儀表讀數(shù)，V2、mA2為普通數(shù)字萬用表（同時用兩個表）。該方式所得數(shù)據(jù)應(yīng)是基本準(zhǔn)確的。Afiilent 66519經(jīng)反復(fù)試驗(yàn)和測試得知，升壓電感的感值大小及額定功率等參數(shù)對轉(zhuǎn)換效率及升壓電路的穩(wěn)定工作密切相關(guān)。但是，因手機(jī)的堆疊尺寸所限，無法選用較大功率和感值的元件，所以電路的轉(zhuǎn)換效率始終受到限制，在目前狀態(tài)下，至多能達(dá)到85%

3、左右。下述測試數(shù)據(jù)中，效率稍高的是PT1305/負(fù)載為KOLON屏的情況（綠色數(shù)字）。更多的試驗(yàn)數(shù)據(jù)有待進(jìn)一步研究獲取。IC PNParameterNO SIMIM1IM2IM3IM4IM5IM6IM7IM8Comme nt1、電路構(gòu)成 PT1305/LQH3NPN220NG0L/RB551V -30TE/PT1305(TDK)普通屏VCC(V)17.8617.9017.8217.8317.8417.8617.8717.6817.67IVCC大于30 mA 時，電感嚴(yán)重 發(fā)燙。IVCC(mA)18326263117203337IVbat(mA)11318173161187100121215 ！

4、249！Efficie ncy74.8778.5170.4875.7777.8379.977.7371.4169.1注：當(dāng)電流超過30mA電感發(fā)燙時，Ivcc會緩慢升高到50mA以上，若仍不關(guān)斷電源，電感會冒煙，有燒糊味。2、電路構(gòu)成 PT1305/SWPA3010S100MT/0.58A /RB551V -30TE/PT1305(TDK)高亮屏VCC(V)17.8117.8817.6517.8017.8117.8517.8517.6217.65經(jīng)10分鐘大電流考 驗(yàn)，無電感 發(fā)燙現(xiàn)象。IVCC(mA)18.183.0526.0525.2829.1017.1621.1531.4534.10IV

5、bat(mA)11519165159183104128198218Efficie ncy74.0975.5373.3374.4874.5377.5177.6273.6572.653、電路構(gòu)成 PT1305/SWPA3010S100MT/0.58A /RB551V -30TE/PT1305(KOLON)VCC(V)17.8217.8817.7017.7317.7417.8417.8017.7317.74經(jīng)10分鐘大電流考 驗(yàn)，無電感 發(fā)燙現(xiàn)象。IVCC(mA)15.504.9526.1031.0032.5019.3025.5529.6031.00IVbat(mA)104.652815817218

6、6107138169180Efficie ncy69.4683.1876.9484.0981.5784.6886.7381.7280.4LM2733(TDK)高亮屏(普軟件)VCC(V)18.1618.1917.8718.1318.1518.1618.1617.8517.80IVCC大于25mA，電感發(fā)燙。IVCC(mA)18.353.0826.1525.7229.6517.3821.3331.8334.75IVbat(mA)14423216203236119150265296！Efficie ncy60.9064.1056.9360.4560.0169.8067.9656.4254.99LQ

7、H3NPN220NG0LMP1541(TDK)普通屏VCC(V)16.8616.8416.8716.8716.8616.8616.8616.8716.85IVCC大于20mA 時，電感急劇升溫IVCC(mA)17.782.9225.7125.2629.6217.0020.5532.0935.25IVbat(mA)921912912313991107153163！Efficie ncy85.7568.1188.4891.1794.5582.8985.2193.1195.89注：在升壓芯片的 Vbat端串入電流表對電路工作有影響，上述測量結(jié)果不太準(zhǔn)確。MP1541(TDK)高亮屏VCC(V)17.

8、8718.0217.8217.7817.7017.9517.8717.7517.68IVCC(mA)18.243.0526.3525.3229.0017.2521.1532.0034.42IVbat(mA)11822173165185114138210221Efficie ncy72.6965.7471.4371.8073.0271.4872.0771.1872.46LQH3NPN220NG0LMP1541(KOLON)VCC(V)16.8616.8416.8616.8216.8416.8616.8516.8516.82IVCC大于 25mA 時，電感22uH急劇發(fā)燙。IVCC(mA)14.5

9、54.8824.7530.0631.2218.4824.7828.6129.95IVbat(mA)7830118160162105132151158Efficie ncy82.7672.0993.0683.1685.4078.0983.2484.0283.90SWPA3010S100MT/0.58AMP1541(KOLON)VCC(V)16.2816.6316.1016.0015.9616.8816.9016.9016.90測VCC電流時，負(fù)載較大VCC顯著下降IVCC(mA)12.594.6721.3227.7528.6?16.8822.8526.1226.95IVbat(mA)6521.6

10、104.2133135VBAT接電池塊時VCC正常，但是IVbat暫無法測量Efficie ncy82.9895.7590.9986.6988.98電源內(nèi)阻影響VCC輸出電壓SWPA3010S100MT/0.58AKTC218(KOLON)VCC(V)17.3117.3117.2917.2517.2517.2617.2617.2617.25IVCC(mA)14.814.8825.1030.4631.6218.7225.0028.9830.1IVbat(mA)9031150182189111150173180Efficie ncy74.9671.7176.1475.9776.0276.6075.

11、7076.0975.91LQH3NPN220NG0LKTC218(TDK)普通屏VCC(V)17.2817.3317.2417.2417.2317.2417.2417.2317.23IVCC 大于 25mA時，升壓電 感有發(fā)熱。IVCC(mA)15.254.9325.7230.5831.8818.8525.1829.1830.35IVbat(mA)11129151187182103141167178Efficie ncy62.4877.5377.2874.1979.4283.0381.0279.2377.31LQH3NPN220NG0LMP1541(KOLON)VCC(V)16.8616.83

12、16.8716.8616.8716.8716.8716.8716.84IVCC 漸近 30mA時，電感急劇發(fā)燙。IVCC(mA)14.714.8525.0530.0231.3218.5624.7728.6529.72iVbat(mA)8132125163164107138155163Efficie ncy80.5867.1388.9781.7184.7877.0179.6982.0680.80萬用表串入升壓板的 Vbat回路測量電流時對芯片工作有影響，上述數(shù)據(jù)不太準(zhǔn)確。LM2733 (VCC(V)15.2515.2815.2615.2515.2515.2615.2515.2515.25新?lián)QKO

13、LON)IVCC(mA)14.184.0623.821.723.413.721.224.524.3FPC與TDK 一 致 0426iVbat(mA)82.148.2144133140.594.3129.5146146Efficie ncy69.3133.8766.3765.4866.8458.3465.7067.3466.79手機(jī)未插SIM卡，關(guān)閉屏蔽室門、VCC為16.5V時播放T卡中視頻，整機(jī)電流（采樣積分）約為180-200毫安，最大電流為542.9毫安。注：聯(lián)想的樣機(jī)（VCC為16.5V,TDK普通屏）播放同樣的視頻文件的整機(jī)電流為200-240毫安，最大860.9毫安。PT1305(

14、KOLON)VCC(V)16.47516.516.4516.4616.4816.4916.4816.4716.48新?lián)QFPC與TDK 一 致 0426IVCC(mA)14.74.1524.822.3241421.725.3725.2IVbat(mA)90.84716314615599.5142163.2162Efficie ncy70.238.365.8666.1667.1561.0666.2767.3866.79KTC218 -DEMO 仃DK) 高亮屏VCC(V)17.1117.0217.0716.9816.9517.0016.9816.9316.95DEMO 板所用電感和二極管體積過大I

15、VCC(mA)17.623.0325.3224.3627.7016.4020.6330.4032.50IVbat(mA)90.516.8130124.5141.584105.4155167Efficie ncy87.6680.7887.4987.4387.3287.3487.4687.3886.81LM2733(TDK)普通屏VCC(V)18.1818.2018.1718.1718.1618.1718.1718.1618.14IVCC大于30mA，電感發(fā)燙。IVCC(mA)18.052.9225.9525.9230.3017.2020.7533.1037.4 ！IVbat(mA)11320.4

16、177162190102125219261！Efficie ncy76.4268.5670.1076.5176.2180.6379.3772.2368.40RT9284A(TDK)高亮屏VCC(V)17.4817.7317.1617.3717.2817.617.5517.116.85IVCC(mA)17.863.0324.224.5227.816.7520.829.831.6IVbat(mA)12722175176201115147216228Efficie ncy64.6964.2662.4563.6862.8967.4665.3562.0861.46SWPA3010S100MT/0.58A

17、LM2733(KOLON)VCC(V)18.1718.2018.1618.1418.1618.1618.1718.1618.15經(jīng)10分鐘大電流考 驗(yàn)，無電感 發(fā)燙現(xiàn)象。IVCC(mA)15.954.9527.2231.3833.0019.5825.7530.0831.42IVbat(mA)11335202232236130180221228Efficie ncy67.4967.7464.4064.5766.8271.9868.4065.0565.82KTC218(TDK)高亮屏VCC(V)17.417.317.2817.2017.2017.2317.2117.2217.21IVCC(mA)17.753.0325.8024.6528.1516.6520.8031.0533.15IVbat(mA)102.519.2149142.516296.5120179191Efficie ncy79.2971.8578.7478.3078.6578.2378.5078.6178.61根據(jù)前期的試驗(yàn)和測試結(jié)果，可以初步確定器件選型為一一PT1305/KTC218、LQ