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ّ֑ӊĂ٫ૣன ਈቨಹLj ؞ሟ۵٫ૣቨ MAX1954A
19-3154; Rev 1; 5/05 ৰۇ భᄋຶ ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ____________________________ ߔऒ໎၂ MAX1954A ༀԧሿૣĂ٫ૣனୀਝٻቨ(PWM) buck ਈ ቨಹᅳᅋ وMAX1954 ᄧहࣼ൛Ljคᅋᅢኢቺ֑ӊࣆ֧ و؍ᄮᅋă ♦ ٫ૣனਈቨಹ MAX1954A ޠዷᅢ 3.0V ባ 13.2V وพ൩٫ႅ۶ཙLjพ൩۶ ཙᅳ IC ޥ٫ྐߔăพ־٫ႅዮّ৹ٻባ 0.8VăIC ޠዷᅢ ߈ وڊ300kHz ߔ౷ଔLj৹໗ ؕݽޥ25A وพ־٫ૣLj ပଔ ؕݽ95%ăሦਞਈቨಹᅘ־ඇ๊وຢᄮLjᄜۚऩ ّષڶพ־٫൛وეഓă ♦ ߈ڊ౷ଔ PWM ♦ ሟ۵٫ૣቨ ♦ พ־ዮّ৹ٻॎባ 0.8VLjFB ॽ ڪ±1% ♦ 3.0V ባ 13.2V พ൩٫ႅ ♦ 300kHz ߔ౷ଔ ♦ 25A พ־٫ૣ MAX1954A ؞ᅘሟ۵٫ૣቨޢLjᇀพ߹־ᆾࢪڮ ଁ෫৹ኚऩّพ൩٫ૣࣆಹऔࠞޢă ♦ 93% ပଔ ߹ԣխࣆߔڱਈቨ(COMP)พ൩ᄧहLjׅષཛྷྥ܅ ؙಹ໗ޥԣխ༶Ljࡱ৹ّݡᄧहჾߔڱኪࡳಹăพ൩ ႅຐޢڊ৹വүಹऔᇀ٫ᆚ٫ႅټମ෫ቁիޠዷLj ܀ቛ༶ԩޢଔ MOSFET ߹െăԩืዖ൫ಶڑ৹ऩّਖ਼ ᅇ٫ૣLjԌॎෛქޔ༶ԩ٫൛ă ♦ ྐၖंૣ٫የ ♦ ّ֑ӊഩ N لޱMOSFET හࣜ ♦ ԩืዖ൫ಶڑ ♦ ဏျ 10 ᄧह μMAX ܢኰ MAX1954A Գᅋཔျ 10 ᄧह μMAX ® ܢኰLj৹ᅘပॎෛ PCB ਅࣺă ________________________________ᄮᅋ ؘᄩࢲᅳஐჱ ____________________________ ྲဳڊ TEMP RANGE PIN-PACKAGE ༐ြࣆญ౷ MAX1954AEUB -40°C to +85°C 10 μMAX PC ᅳܾྣಹ MAX1954AEUB+ -40°C to +85°C 10 μMAX པಹࠥޥ٫ PART +ӹྐೆܢኰă ّႅܖԦ٫ᆚ ٫ဳ/ཌ ____________________________ ᄧहైብ TOP VIEW HSD 1 COMP 10 BST 2 MAX1954A 9 LX FB 3 8 DH GND 4 7 PGND IN 5 6 DL μMAX μMAX ก Maxim Integrated Products, Inc.وኢՋඨӶă ________________________________________________________________ Maxim Integrated Products 1 ӊྲྀก Maxim ቁᄪྲྀዊوᄕྲྀLjMaxim ԥۭڶᄕቲ،ᇀوᄖࢪᅑױդූݘྥؓوᇖăഋኢᄌᄕྲྀቲ৹،ᇀྲྀዖዩቑࢪ ۭᄕؓྥLjၖവ്ൌࠨװᅷوኼവ၂LjഋԸ৬ Maxim ໗وޥᄪྲྀҔዊă www.BDTIC.com/maxim ຏടஊܑჅ౹ࠧዮူҔืوযዊLjഋ ོ܃Maxim وኙოǖwww.maxim-ic.com.cnă MAX1954A ________________________________ ݣะ MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ABSOLUTE MAXIMUM RATINGS IN, FB to GND...........................................................-0.3V to +6V LX to BST..................................................................-6V to +0.3V BST to GND ............................................................-0.3V to +20V DH to LX ................................................... -0.3V to (VBST + 0.3V) DL, COMP to GND.......................................-0.3V to (VIN + 0.3V) HSD to GND..............................................................-0.3V to 14V PGND to GND .......................................................-0.3V to +0.3V Continuous Power Dissipation (TA = +70°C) 10-Pin μMAX (derate 5.6mW/°C above +70°C) ...........444mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range ............................+65°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN = 5V, VBST - VLX = 5V, TA = 0°C to +85°C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS 3.0 5.5 V 3.0 13.2 V 2 mA 2 mA 2.9 V GENERAL Operating Input Voltage Range HSD Voltage Range (Note 1) Quiescent Supply Current VFB = 1.5V Standby Supply Current VIN = VBST = 5.5V, VHSD = 13.2V, LX = unconnected, COMP = GND Undervoltage-Lockout Trip Level Falling VIN, 50mV (typ) hysteresis 2.5 Maximum output voltage depends on external components and maximum duty cycle 0.8 1 2.7 DC-DC CONTROLLER Output-Voltage Adjust Range (VOUT) V ERROR AMPLIFIER FB Regulation Voltage Transconductance -1.0 +0.8 +1.0 70 110 160 Voltage Gain 200 FB Input Leakage Current VFB = 0.9V 50 % μS V/ V 500 NA FB Input Common-Mode Range -0.1 +1.5 V COMP Output-Voltage Swing 0.80 2.36 V Current-Sense Amplifier Voltage Gain 3.15 3.5 3.85 V /V VFB = 0.8V 110 135 145 VFB = 0V 21 36 51 Current-Limit Threshold VPGND - VLX mV OSCILLATOR Switching Frequency MAX1954A 240 300 360 kHz Maximum Duty Cycle Measured at DH 89 91 93 % Minimum Duty Cycle VCOMP = 1.25V, LX = GND, VBST = VIN = 3.3V 2.5 3 % 2 _______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ (VIN = 5V, VBST - VLX = 5V, TA = 0°C to +85°C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS SOFT-START Soft-Start Period 3.4 ms Soft-Start Levels 12.5 mV FET DRIVERS DH, DL Output Low Voltage DH, DL Output High Voltage ISINK = 10mA 0.1 VIN - 0.1V or VBST - 0.1V ISOURCE = 10mA DH Pullup/Pulldown, DL Pullup On-Resistance DL Pulldown On-Resistance LX, BST, HSD Leakage Current V V 1.5 3 Ω 1 2 Ω 30 μA VBST = 18.7V, VLX = 13.2V, VIN = 5.5V, VHSD = 13.2V THERMAL PROTECTION Thermal Shutdown Rising temperature, 15°C hysteresis °C +160 SHUTDOWN CONTROL COMP Logic-Level Low 3V < VIN < 5.5V COMP Logic-Level High 3V < VIN < 5.5V 0.25 V 100 μA MAX UNITS 3.0 5.5 V 3.0 13.2 V 0.8 V COMP Pullup Current ELECTRICAL CHARACTERISTICS (VIN = 5V, VBST - VLX = 5V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER CONDITIONS MIN GENERAL Operating Input Voltage Range HSD Voltage Range (Note 1) Quiescent Supply Current VFB = 1.5V 2 mA Standby Supply Current VIN = VBST = 5.5V, VHSD = 13.2V, LX = unconnected, COMP = GND 2 mA Undervoltage Lockout Trip Level Rising VIN 3% (typ) hysteresis 2.93 V 2.50 DC-DC CONTROLLER Output-Voltage Adjust Range (VOUT) 0.8 0.9 x VIN V -2.5 +1.0 % 70 160 μS 500 NA ERROR AMPLIFIER FB Regulation Voltage Transconductance FB Input Leakage Current VFB = 0.9V FB Input Common-Mode Range -0.1 +1.5 V COMP Output-Voltage Swing 0.8 2.2 V _______________________________________________________________________________________ www.BDTIC.com/maxim 3 MAX1954A ELECTRICAL CHARACTERISTICS (continued) MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ELECTRICAL CHARACTERISTICS (continued) (VIN = 5V, VBST - VLX = 5V, TA = -40°C to +85°C, unless otherwise noted.) (Note 2) PARAMETER CONDITIONS MIN MAX UNITS 3.15 3.85 V/V VFB = 0.8V 110 145 VFB = 0V 21 51 240 360 kHz 89 93 % 3 % 0.1 V Current-Sense Amplifier Voltage Gain Current-Limit Threshold VPGND - VLX, MAX1954A mV OSCILLATOR Switching Frequency Maximum Duty Cycle Measured at DH Minimum Duty Cycle VCOMP = 1.25V, LX = GND, VBST = VIN = 3.3V FET DRIVERS DH, DL Output Low Voltage DH, DL Output High Voltage ISINK = 10mA ISOURCE = 10mA VIN - 0.1V or VBST - 0.1V V DH Pullup/Pulldown, DL Pullup On-Resistance 3 Ω DL Pulldown On-Resistance 2 Ω 30 μA 0.25 V 100 μA LX, BST, HSD Leakage Current VBST = 18.7V, VLX = 13.2V, VIN = 5.5V, VHSD = 13.2V SHUTDOWN CONTROL COMP Logic-Level Low 3V < VIN < 5.5V COMP Logic-Level High 3V < VIN < 5.5V 0.8 COMP Pullup Current Note 1: HSD and IN are externally connected for applications where HSD < 5.5V. Note 2: Specifications to -40°C are guaranteed by design and not production tested. 4 _______________________________________________________________________________________ www.BDTIC.com/maxim V ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ MAX1954A _________________________________________________________________ ٨ျޠዷ໎၂ (TA = +25°C, unless otherwise noted.) OUTPUT VOLTAGE vs. LOAD CURRENT OUTPUT VOLTAGE (V) EFFICIENCY (%) VOUT = 1.5V 70 60 2.55 2.50 2.45 50 VIN = VHSD = 5V VIN = VHSD = 5V 2.40 40 0.1 1 2 3 4 LOAD CURRENT (A) OUTPUT VOLTAGE vs. INPUT VOLTAGE OSCILLATOR FREQUENCY vs. INPUT VOLTAGE 0.80 0.80 VIN = VHSD IOUT = 5A 5 VOUT = 2.5V 10 -10 VOUT = 0.8V -30 -50 VIN = VHSD IOUT = 5A 3.0 3.5 4.0 4.5 5.0 5.5 LOAD TRANSIENT MAX1954A toc06 330 MAX1954A toc05 MAX1954A toc04 0.81 30 INPUT VOLTAGE (V) 350 OSCILLATOR FREQUENCY (kHz) OUTPUT VOLTAGE (V) 1 LOAD CURRENT (A) 0.81 50 -70 0 10 70 MAX1954A toc03 90 MAX1954A toc02 VOUT = 2.5V 80 2.60 MAX1954A toc01 100 OUTPUT VOLTAGE CHANGE vs. INPUT VOLTAGE CHANGE IN OUTPUT VOLTAGE (mV) EFFICIENCY vs. LOAD CURRENT TA = -40°C VOUT AC-COUPLED 100mV/div 310 5A 290 TA = +85°C TA = +25°C IOUT 5A/μs 270 500mA VIN = VHSD 250 0.79 10.8 11.4 12.0 INPUT VOLTAGE (V) 12.6 13.2 3.0 3.5 4.0 4.5 5.0 5.5 40μs/div INPUT VOLTAGE (V) _______________________________________________________________________________________ www.BDTIC.com/maxim 5 MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ____________________________________________________________ ٨ျޠዷ໎၂(ၦ) (TA = +25°C, unless otherwise noted.) NO-LOAD SWITCHING WAVEFORMS LOAD TRANSIENT MAX1954A toc08 MAX1954A toc07 VOUT AC-COUPLED IL 2A/div DH 10V/div LX 5V/div DL 5V/div 100mV/div 5A IOUT 5A/μs 2.5A 2μs/div 40μs/div HEAVY-LOAD SWITCHING WAVEFORMS ILOAD = 5A POWER-UP/POWER-DOWN WAVEFORMS MAX1954A toc10 MAX1954A toc09 IL 2A/div DH 10V/div LX DL VIN 5V/div 5V/div VOUT 2V/div 5V/div ILX 5A/div 4ms/div 2μs/div STARTUP INTO PREBIASED OUTPUT (OUTPUT PREBIASED AT ~1.7V) SHORT CIRCUIT AND RECOVERY MAX1954A toc11 VOUT 1V/div VIN 2V/div IIN 2A/div VOUT 1V/div VIN 5V/div DH 5V/div DL 5V/div 5A/div ILX 200μs/div 6 MAX1954A toc12 2ms/div _______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ᄧह ண֎ ޢ 1 HSD 2 COMP 3 FB 4 GND 5 IN IC٫ᆚ٫ႅăཛྷICޥ٫ă৹ઘेف3Vባ5.5Vቐࣺو٫ᆚăᅋქޔ0.22μF໋ׯ٫൛సଁባGNDLjᅋქޔ1μF ໋ׯ٫൛సଁባPGNDă 6 DL ّӫᇨࣁഝڑพ־ăഝڑༀԧሿૣMOSFETăᇀ0ባVIN ቐࣺ҈ڑăᇀߔࣆڱUVLOኴຢ࿒DLཛྷّă 7 PGND 8 DH ݽӫᇨࣁഝڑพ־ăഝݽڑӫNلޱMOSFETăDHཛྷܿڑഝڑಹพ־LjᇀVLX ባVBST ቐࣺ҈ڑă ᇀߔࣆڱUVLOኴຢ࿒DHཛྷّă 9 LX ਈቨಹ٫ૣंՌพ൩ăटLXઘेባMOSFETࠧ٫وݮઘे٧ăLXཛྷૣ٫ଁوԸ৬٧ă 10 BST ݽӫࣁ٫ૣंՌพ൩ăHSDंՌݽӫNلޱMOSFETࣁණو٫ႅă৹ෳᅋ(ྲྀKelvin)ઘे۽ेባݽӫ MOSFETࣁă ԣխࣆߔڱਈቨᄧहă৹ઘेคوصRCཌԣխਈቨଁă࿒ባٜ৹ߔڱICăᅘߔRCࣜوഋԸऑ ԣխහࣜԩܖă ۴ਯพ൩ăٻॎባVFB = 0.8VăटFBेባქޔพف־GNDቐࣺو٫የܖႅಹوቲဲֱ་ჾහڊพ־٫ႅă ٜă ޢଔٜă ݽӫMOSFETഝڑಹ٫ᆚพ൩ăᇀBSTᅳLXቐࣺઘेქޔ0.1μF໋ׯ٫൛ੂཛྷݽӫNلޱMOSFET໗ޥӤეوᇨ ࣁഝڑă ____________________________ ࿈ํட MAX1954A กةพ־Ă٫ૣனĂ PWM ऩႅျ DC-DC ਈቨಹLj؞ᅘሟ۵٫ૣቨLjޠዷᅢ 300kHz ߔ౷ଔ ჾࢩݽهပଔăMAX1954A හࣜᅋੂഝڑༀԧ buck ༬ ቲوქڶ༶ԩ N ޢلޱଔ MOSFET Ljृቐࢱᅢ P ޢلޱ ଔ MOSFET و༬ᅘوݽޚပଔ֑ࠧوّޚӊăّӫ MOSFET ـو٫የӇᅋੂंՌ߆ଁڮሓLjۚݽӫ MOSFET ـو٫የᇘӇᅋᅢ٫ૣன۴ਯLjᄜྐױၖ ෳᅋंૣ٫የăଁڮ٫ૣ߈ڊᇀ 135mVăሟ۵ૣ۽ Ѧऩّષࣆଁڮႛቺ߹ᆾഉਦ࿒وพ൩٫ૣăMAX1954A ైᅘქݽޔӫࣁพ൩(HSD)Ljᆰၛ 3V ባ 13.2V وਝพ൩ ۶ཙLjԌڢᅢ IC พ൩٫ᆚ(༐ 1)ă DC-DC ኪࡳಹਈቨࣲ MAX1954A ऩႅျኪࡳಹԳᅋ PWM ٫ૣனਈቨ۽Ѧă ԩਗؙ܅ـಹजಲქྥޔ٫ႅܖࢵوăქޔ ӔृಹӔृࢵوࡍܖ٫ႅ۴ਯဳࠟᅳࣩڂષဟଔԣխဳ ࠟوࡍؙ܅و٫ૣݮᄮဳࠟLjᇀኙ PWM Ӕृಹቲࣩ൩ဟ ଔԣխกཛྷષүེ֞ڊԌဋׅ٫ݮो໓ăᇀԩ෫ ትو୧ქޔණෙႤLjݽӫ MOSFET ـLjቓባ PWM Ӕृ ಹӇفؕࢪۢዮؙሀਅӔăᇀـಜࣺLj߹٫وݮ ٫ૣ၂తෙLjटફ،فթቲԌཛྷพ־໗ޥ٫ ૣă٫ૣன۴ਯ࿅༇ޗযพ־٫ႅྥوဳࠟٻॎܥ ٫ݮ٫ૣăሿޔ٫ଁޠوዷ੮ᅢქޔߔனਗـ ؙ܅ಹLjᄜཛྷ౿ো٫ݮ٫ૣे॰ᅢܥ٫ݮ٫ૣ(࣯හ٫ ݮફዣؙLjᄜۚෳླྀԒ٫ૣዣဏ)ăሦটट٫ႅன PWM ቲիऑ وLC କԒಹࣁ٧༚ဂوݽޚ౷ଔă _______________________________________________________________________________________ www.BDTIC.com/maxim 7 MAX1954A ____________________________________________________________________ ᄧहํட MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ___________________________________________________________________ޢਢ༐ IN THERMAL LIMIT SHUTDOWN COMPARATOR UVLO MAX1954A SLOPE COMPENSATION 0.5V HSD COMP 2.36V CLAMP ERROR AMPLIFIER BST FB PWM CONTROL CIRCUITRY DH CURRENTSENSE CIRCUITRY LX IN DL CURRENT-LIMIT COMPARATOR REFERENCE AND SOFT-START DIGITAL-TO-ANALOG CONVERTER PGND SHORT-CIRCUIT CURRENT-LIMIT CIRCUITRY CLOCK FOLDBACK CURRENTLIMIT CIRCUITRY GND ᇀ෫ትቾಜࡍوҙቾLjݽӫ MOSFET ߔّۚڱӫ MOSFET ـăዅ٫ૣ࿒ऩ٫ݮኒङงٸ܅ຑ،وફLjༀ ෫ཛྷพ־໗ޥ٫ૣăص٫ݮ٫ૣմ־ຑၖݘᆾ٫ૣ෫พ ־٫൛֬٫Ǘۚص٫ݮ٫ૣृّ෫ᇘ܅٫Ljۚ౿ࡤݘ ᆾوڭ٫ႅăᇀ߹ᆾഉਦ࿒Ljص٫ݮ٫ૣմ߹٫ૣ ෫(Ըऑૣ٫ଁԩ)ܖLjݽӫ MOSFET ԥᆿᇀ෫ትණෙႤ ؘLjّۚӫ MOSFET ᇘү֞ـჾෳ٫ݮ٫ૣ࿒ऩă MAX1954A ޠዷᅢቨ PWM னLjྐଥݘᆾࠨਈቨಹ ቷү֞࠽وڊߔ౷ଔLjෳࡍڭߔᇑକԒಹوහ ࣜޚ൛ᄁă 8 ٫ૣंՌؙ܅ಹ ٫ૣंՌ٫ଁؙ܅٫ૣݮᄮ٫ႅ(ݽӫ MOSFET ـو٫ የ RDS(ON)֓ჾ٫ݮ٫ૣ)ăوࡍؙ܅٫ૣݮᄮဳࠟᅳԩ ဟଔԣխဳࣩࠟࡍ (V SUM ) ൩ PWM Ӕृಹو۴ဂพ ൩ă صVSUM մ߹۴ਯ٫ႅ(ܖࢵوVCOMP)ࡍ PWM Ӕृಹ ߔݽڱӫ MOSFET ăݽӫ MOSFET ᄮॳ৹৯॰ਈቨಹ Ѡ܅LjԌᅋྲྀઘेट HSD ࣆ LX ᅳ MOSFET ઘLjჾ үቆ٫ૣंՌॽڪԌ໗ڊེݽ၂ă _______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ C1 VIN 3V TO 5.5V C2 C3 D1 IN VHSD 5.5V TO 13.2V HSD N1 BST DH C4 L1 MAX1954A LX RC COMP R1 R3 DL CF CC VOUT 1.8V C5 C6 PGND R2 GND FB ༐ 1. MAX1954A ٨ျᄮᅋ٫ଁ VHSD 10.8V TO 13.2V VIN 3V TO 5.5V D1 HSD C1 0.22μF IN BST C15 C2–C6 10μF N2 DH C7 0.1μF MAX1954A RC 270kΩ L1 0.8μH VOUT +1.8V AT 20A LX N3 COMP CC 560pF N1 CF 15pF N4 R3 DL R1 10kΩ C14 C8–C13 270μF PGND R2 8.06kΩ GND FB ༐ 2. ᅘ 20A พ و־MAX1954A ٫ଁ ૣ٫ଁ ૣ٫ଁԳᅋྐຈࠞĂሟ۵Ă߄٫ૣቨۨLjԳᅋّ ӫ MOSFET ـو٫የዷཛྷंՌᆐऔăݽصӫ MOSFET ߔࡍڱLjࣶญّӫ MOSFET وڭ٫ႅă߷ّ MOSFET وڭ٫ႅ (R DS(ON) x I INDUCTOR ) ԥմ߹٫ૣLjݽӫ MOSFET ৹ቁիؘăᇀױഉਦ࿒Ljพ־౿ࡤ࿒ऩմ־ ེႅ۶ཙă߷صქوူ״ስظಹቾಜ෫ّӫ MOSFET وڭ٫ႅմ߹٫ૣۧLjᇘّӫ MOSFET ү֞ـۚݽӫ MOSFET ү֞ߔڱă _______________________________________________________________________________________ www.BDTIC.com/maxim 9 MAX1954A ___________________________________________________________________٨ျᄮᅋ٫ଁ MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ صพ־Ӈଁڮ෫Ljሟ۵ૣ٫ଁट٫ૣۧ၂ٜऋ ඵባቁի و20%Ljჾऩّಹऔࣆࠞޢพ൩٫ૣăّصӫ MOSFET وڭ٫ႅّᅢ٫ૣۧࡍLjݽӫ MOSFET ࣊ᅢ࿒ქޔ෫ትቾಜؘăᇀႛቺ߹ᆾࣆଁڮഉਦ࿒Lj MAX1954A وߔޠዷ౷ଔट࿒ऩLjᄜཛྷّӫ MOSFET ـو෫ࣺ࢙մ߹ქޔ෫ትቾಜă٫ૣۧӇᆊብཛྷ 135mVă ߄ׅ٫ૣቨ༶LjMAX1954A ࡱᄽᅘኒቾಜܥ٫ૣ ޢLj߹ቷቛـ෫ࣺੂቨݽӫ MOSFET وڭ ٫ႅăױޢᆿࣩණሟ۵߄٫ૣቨLj໗ޥષქޔ ܇ի৹৯߹وᆾࣆଁڮүă ႅຐ(ڊUVLO) ߷ V IN ټባ 2.7V ჾ࿒Lj MAX1954A ট്ཛྷ٫ᆚ٫ႅ߹ ّLjྐۨෳ٫ଁቁիޠዷLj߆ UVLO ٫ଁट९ቛߔՃዷ Ԍट DL ࣆ DH ᇨࣁഝڑಹባّă صVIN ෙݽባ 2.7V ჾණ ࡍLjਈቨಹ࣊६൩ಶ֔ڑၠԌቺူቁիޠዷă ಶڑ صVIN ݽᅢ UVLO ୭ࡍLjMAX1954A ࣊৹ჾಶڑߔՃ ዷăدਈቨಹوෳࡱეୄዣჾ࿒ 5 ޔऔǖ 1) VIN մ߹ 2.7V UVLO ୭Ǘ 2) ԩԸ৬մ߹ڊې و92% (VREF > 1V)Ǘ ༀԧሿૣഝڑಹ(DL) 3) ԩ౭ብ٫ଁණ٫Ǘ ᅋّየ MOSFET ༀԧሿૣಹؠໜիߢوဒ໎ࢱሿૣ۠ࣁ ߘ৹ჾऩّሿૣಹቲـבوຈࠞăMAX1954A ࡱઉᅋༀ ԧሿૣಹੂүቆዔফᇨࣁഝڑ٫ଁوቁիಶڑLjԌᅋດ ੂ໗ޥૣဳࠟă DL ّӫഝڑԒြዜกࠧ DH ݽӫഝڑ Ԓြԣ(ᅘถਈو๘ഘ෫ࣺჾ܀यՐـࢪቓ)ă๘ ഘ෫ࣺ٫ଁࣶญ DL พ־Ljየቛݽӫ MOSFET ᇀ DL ༾ഩߔ ڱჾـăཛྷෳ๘ഘ෫ࣺ٫ଁቁիޠዷLjᇀ DL ഝڑಹ ባ MOSFET ᇨࣁቐࣺӤၙᅘქّየĂّݮଁăܱ ᇘLjॳߘᇨࣁࡱ،ᅘ٫ࠣLjMAX1954A ቲंوՌ٫ଁᅘ ৹࢙ྥ്ཛྷ MOSFET ᇨࣁ჻ߔڱăᄮෳᅋ࠶ڮೲਝو ઘ(߷ MOSFET লಹऔ 1 ᄪ؍ჾණLjਝڪᄮᇀ 50mil ባ 100mil)ăದດႤ(DH ߔو)ڱ๘ഘ෫ࣺნก߹ंՌᇨࣁ വوڊă 4) སմ߹െ߹ᆾࣁǗ ݽӫᇨࣁഝڑ٫ᆚ(BST) 5) ۴ਯ٫ႅّᅢٻሿ୭ă ߷ୄዣჾණሦဗऔLjᇘऩႅਈቨಹ࣊൫ಶڑԌ ६൩ߔٻሿኴຢă൫ಶڑ٫ଁኒङຝݽพ־٫ႅLjቓ ባ FB ණو٫ႅٌᅢԸ৬٫ႅă߹ڶพ־٫ႅණෙڪ وਈቨLjऩّષಶ֔߹ڑቲوพ൩ਖ਼ᅇ٫ૣă൫ಶڑ෫ ࣺཛྷ 1024 ޔ෫ትቾಜ(1024 / fS)Ljพ־٫ႅႤዅ 64 ޔٌ وພोኒङෙݽăྐଥพ־٫൛ࣆݘᆾࠨLj൫ಶڑ༾ ֑ࡍพڊེف࢙ؕڞ־ă MAX1954A ࡱᄽᅘᄮوԩ٫ଁੂ܀ቛᇀ൫ಶࢪڑ UVLO ಜࣺڶ჻ॿ֬٫وพ־٫൛܅٫ăױ໎၂(ٻةಶ )ڑᇀ MAX1954A وพ־ᅳದຓ٫ᆚوพ־Ԍખوᄮᅋቲ กӤეوLjઋ൝ᅨ٫ᆚࢪᅘࢲأ٫ᆚوᄮᅋă ݽӫ N لޱߔوᇨࣁഝڑ٫ႅกᅑܿڑ٫൛ዔফ٫ଁդ ූ(و༐ 3)ăّصӫ MOSFET ـ෫LjBST ᅳ LX ቐࣺو٫ ൛Ӈ V IN ٫ᆚ֬٫ባ V IN ऋണქߘࣁ۠ޔႅऩăّصӫ MOSFET ߔӡ෫Lj٫൛ቲ،و٫ႅࣩڂᇀ LX ٫ණLj ཛྷݽӫ MOSFET ໗ޥӤეـو٫ႅ (V GS ) ăഹࡍਈቨ ಹेქޔઘेᇀ BST ᅳ DH ቐࣺوԩߔੂؘݽӫ MOSFETă IN BST DH MAX1954A N LX DL N ༐ 3. DH ዔফ٫ଁ 10 ______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ MAX1954A ӹ 1. ༚ऌಹऔ MAX1954A (FIGURE 1) PART DESIGNATOR 20A CIRCUIT (FIGURE 2) C1 0.22μF, 10V X7R ceramic capacitor Kemet C0603C224M8RAC 0.22μF, 10V X7R ceramic capacitor Kemet C0603C224M8RAC C2 1μF, 6.3V X5R ceramic capacitor Taiyo Yuden JMK212BJ106MG 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN C3 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN C4 0.1μF, 6.3V X7R ceramic capacitor 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN C5 180μF, 4V SP polymer capacitor Panasonic EEFUEOG181R 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN C6 1500pF, 50V X7R ceramic capacitor TDK C1608X7R1H152K 10μF, 16V X5R ceramic capacitor Taiyo Yuden EMK325BJ106MN C7 — 0.1μF, 50V X7R ceramic capacitor Taiyo Yuden UMK107BJ104KA C8 — 270μF, 2V SP polymer capacitor Panasonic EEFUEOD271R C9–C13 — 270μF, 2V SP polymer capacitors Panasonic EEFUEOD271R Cc 680pF, 10V X7R ceramic capacitor Kemet C0402C681M8RAC 560pF, 10V X7R ceramic capacitor Kemet C0402C561M8RAC CF — 15pF, 10V C0G ceramic capacitor Kemet C0402C150K8GAC R1 16.9kΩ ±1% resistor 10kΩ ±1% resistor R2 8.06kΩ ±1% resistor 8.06kΩ ±1% resistor R3 2Ω ±5% resistor — RC 62kΩ ±5% resistor 270kΩ ±5% resistor D1 Schottky diode Central Semiconductor CMPSH1-4 Schottky diode Central Semiconductor CMPSH1-4 N1, N2 20V, 5A dual MOSFETs Fairchild FDS6898A 30V N-channel MOSFETs International Rectifier IRF7811 N3, N4 — 30V N-channel MOSFETs Siliconix Si4842DY 1μH, 3.6A inductor TOKO 817FY-1R0M 0.8μH, 27.5A inductor Sumida CEP125U-0R8 L1 ______________________________________________________________________________________ www.BDTIC.com/maxim 11 MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ߔڱ MAX1954A ࡱᅘّڱߔࠞޢனăઉᅋქࣅޔ٫ࣁ ଁ وNPN ॹߘट COMP ّ৹ߔ ڱIC ăCOMP Ӥၙ ّባ 0.25V ჾ࿒ԯߔ ڱMAX1954Aă৹ၭᇗქ ޔVCE(SAT) ّᅢ 0.25V ॹوߘăߔڱ෫Ljพ־ཛྷݽየ৩ăߔڱன ৹टຢ٫ૣ(IQ)ऋඵባ 220μA (٨ျ)ăഋኢᄌLjჾױ ቸ۽ߔڱ෫Lj४ص٫ݮફᅋॳࡍพ־ԯ࢙܅٫ăࢎ ޠݒዷ෫ୣᅘ൫ಶ֔߹ڑăቝᅘصሟ۵٫ૣӇۢ ෫ԯ࢙ᄧಲལ൫ಶڑனă ဋऩّयૣ٫౿ຑࠝوفهă৹ԳᅋქޔѠኰ فቚڊਅࣺLjᅞᅘዮّቓૣ٫የّوຈࠞ٫ݮă Ⴡာ٫ݮիกዮࣧၭᇗăدܛာ٫ޚݮཛྷચࣱLj ნ৹࠶ٜࠝޠዷᅢ 300kHzăຑၭ٫ڊېوݮұࠧ٫ૣӤ ၙմ߹ᅑ࿒വܥوڊ٫ૣǖ ⎛ LIR ⎞ IPEAK = ILOAD(MAX ) + ⎜ ⎟ × ILOAD(MAX ) ⎝ 2 ⎠ හብ٫ૣ െ߹ᆾү െ߹ᆾүቨሿ ޔMAX1954A ࠞޢوăصॕུմ߹ T J = +160°C ෫Ljԩུݮבڪಹटߔ ڱIC Ljෳದੲലă صॕུ࿒ऩ 15°C ࡍLjུݮבڪಹ࢙ቺူಶ ڑICLjᄜױᇀ ઘၦെ߹ᆾഉਦ࿒LjIC टդූڱၦพ־ă ____________________________ හࣜԧኊ MAX1954A Գᅋ߄٫ૣंՌۨ۽६ှૣăّӫ MOSFET ـ٫የණوႅऩӇᅋੂंՌ٫ݮ٫ૣăᇀ I LOAD(MAX) ࿒Ljّӫ MOSFET ႅऩ߄و٧ཛྷǖ ⎛ LIR ⎞ VVALLEY = RDS(ON) × (ILOAD(MAX) − ⎜ ⎟ × ILOAD MAX ) ⎝ 2 ⎠ ( ) ࣜ و־VVALLEY Ӥၙဏᅢߢوڊዮဏ٫ૣۧă හብพ־٫ႅ ეහብ MAX1954A وพ־٫ႅLj৹ट FB ᅳქޔઘेᇀพ وڭ־༶ԩ٫የܖႅಹوቲ٧ઘ ( ༐ 1 ࣆ༐ 2) ă৹ၭᇗ R2 ढ़ᅢ 8kΩ ባ 24kΩ ቐࣺLjԌѢ࿒ࣜ R1ǖ ⎛V ⎞ R1 = R2 × ⎜ OUT − 1⎟ ⎝ VFB ⎠ RDS(ON) < 0.8V / (3.65 x (ILOAD(MAX) x ( 1 + LIR / 2))) ᄮԳᅋ MOSFET ᇀᆊಜوዮޠؙዷॕུ࿒وዮ ؙRDS(ON) ăქۨوࠝृޔᇘกLj MOSFET ॕུ୧ෙݽქڪ٫የ ᇜࣩ 0.5%ă MOSFET ၭᇗ ದቲ VFB = 0.8VLjR1 ࣆ R2 ᄮॳ৹৯॰ IC Ԧብă ٫ݮ ᇀৈڊၭᅋࠨቸ٫ݮ෫LjၖंՓჾ࿒࣎ޔԸืLj࣊ǖ พ൩٫ႅĂพ־٫ႅĂݘᆾ٫ૣĂߔ౷ଔࣆ LIRăLIR ཛྷ٫ݮ٫ૣླྀԒᅳቓૣݘᆾ٫ૣوӔăृ وݽLIR ᆰ ၛԳᅋृဏو٫ݮLjـ࢙دቤوݽޚຈࠞࣆوؙޚพ־ ླྀԒă֧؍ᅳပଔቐࣺوქޔӔृࠝوሟቶก 30% وLIRă ၭڊຑᅘԸืࡍLj৹Ѣ࿒ࣜ٫ݮǖ VOUT × (VIN − VOUT ) L= VIN × fS × ILOAD(MAX ) × LIR ದቲ fS ཛྷߔ౷ଔă৹ၭᇗქेޔ॰ࣜوӶኼă٫ ݮॽوവڪԌԥቺეLjۚೲࡱ৹ჾޗয֧؍Ă֑ӊࣆ ပଔوეഓ६ှٻሿăृّو٫ݮ৹ऩّ٫؍֧وݮ ࣆ֑ӊLjدༀ෫ნ࢙ᅑᅢृܥوݽ٫ૣۚෳพླྀ־Ԓ ࣩࣆؙပଔऩّăქ۽எLjृوݽ٫ݮ࢙໗ݽပ ଔLjدᅑᅢၖეوۂޚതLjየ၂ຈࠞوᇜࣩዮቷ࢙ٚ 12 ױ༶Ljݽӫ MOSFET RDS(ON)Ӥၙୄዣ࿒Ljჾஊ߹ᇍٜ ܥۢ٫ૣ٫ଁǖ MAX1954A ഝڑޔ༶ԩوࣃ٫౿Ă N لޱMOSFET ዷཛྷߔᆐऔăߔऒԸืၭᇗཛྷǖ 1) ـ٫የ (R DS(ON))ǖᆣّᆣࠝLjدዮݘؙᆾ෫و٫ૣ ंՌဳࠟ(RDS x IPEAK)Ӥၙؙᅢ 16mV Ǘ 2) ዮؙljᆚ٫ႅ (V DSS) ǖባඵᄮӔݽӫ MOSFET ࣁ ණوพ൩ᆚ٫ႅ ݽ20% Ǘ 3) ᇨࣁ٫ࠣ(Qg, Qgd, Qgs)ǖᆣّᆣࠝă ڶᅢ 3.3V พ൩وᄮᅋLjᄮၭᇗქޔᇀ VGS = 2.5V ࿒ߢڊ RDS(ON) وMOSFETăڶᅢ 5V พ൩وᄮᅋLjᄮၭᇗქޔᇀ VGS ≤ 4.5V ࿒ߢ ڊRDS(ON) وMOSFETăዷཛྷქޔပଔᅳ ֑ӊቐࣺوનࠝሟቶLj৹ၭᇗქޔᇀڊېพ൩٫ႅࣆพ ־٫ૣ࿒Ljـבຈࠞࠧߔຈٌࠞݽوӫ MOSFET (N1) Ljຑၭ MOSFET Ӥၙᅘୄዣჾණ٫ૣቨऔو R DS(ON)ăڶᅢ N2 Ljᄮവүದԥ࢙ᅑᅢ N1 ـຑդූو dV/dt ۚؓྥـLjሦ࢙ـቤቓ٫ૣۚෳပଔ࿒ऩă Qgd/Qgs ृّ وMOSFET ᅘृ وݽdV/dt ֘ถă ______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ⎛ LIR ⎞ VVALLEY = RDS(ON) × (ILOAD(MAX) − ⎜ ⎟ × ILOAD MAX ⎝ 2 ⎠ ( ) ԳᅋRTDS ࿒( وMAX Lj Use J(MAX) DS(ON) (ON) at TJR ). PN2DC = 2 × ILOAD × VF × t dt × fS ದቲ V F ཛྷ۠ࣁߘوቁဂႅऩLj t dt ཛྷ N1 ࣆ N2 ߔኪࡳ ቐࣺو๘ഘ෫ࣺLjfS ཛྷߔ౷ଔLjtdt ᆢཛྷ 20ns (٨ျ)ă N1 ֬صሀਅӔਈቨߔLjԌᅘჾ࿒ኙეຈࠞǖבلޱ ـຈࠞ (P N1CC ) Ă VL ቺڂߔຈࠞ (P N1SW ) ࣆഝڑຈࠞ (PN1DR)ăN1 ୣᅘ۠ࣁߘـבຈࠞLjᄜཛྷߘࣁ۠ݡԥ ـב٫ૣă ⎞ ⎛V PN1CC = ⎜ OUT ⎟ × I2 LOAD × RDS(ON) ⎝ VIN ⎠ Use at TRJDS(ON) ԳᅋR TDS (ON)࿒و (MAX) .Lj J(MAX) ⎛Q + Q gs gd PN1SW = VIN × ILOAD × ⎜ ⎜ I GATE ⎝ ⎞ ⎟ × fS ⎟ ⎠ ದቲ IGATE ཛྷ DH ഝڑಹ౿োพ־٫ૣLjѢ࿒ࣜǖ IGATE ≅ 0.5 × VIN RDS(ON)(N2) + RGATE ದቲ RDS(ON)(N2)ཛྷݽӫ MOSFET ഝڑಹـو٫የ(٨ျ ཛྷ 1.5Ω)Ljۚ RGATE ᇘཛྷ MOSFET وԩᇨࣁ٫የ(ᆢཛྷ 2Ω)ǖ RGATE PN1DR = Qg × VGS × fS × RGATE + RDS(ON)(N2) MOSFET ืযዊቲԌས६ှ࠶ࠝڊوᄏăԸሙ MOSFET ืযዊቲوെየߢޏLjઉᅋஎࣜࠞޢو־Lj৹ࣜ ־үቆಹऔޠዷᇀᆊಜዮؙॕུ۶ཙຑၖე وPCB எࢵă ཛྷऋඵᅑߔᇑຑդූو٫(ൃݧEMI)Lj৹ᇀݽӫ ߔࣁᅳّӫߔᆚࣁቐࣺᇜࣩქ ޔ0.1μF ׯ໋و٫൛Lj ࢪᇀ DH ࠧ DL ණהખ٫የੂऋࡲߔኪࡳăدᇜࣩהખ ٫የნ࢙ᇜࣩ MOSFET ࠞޢوLjᄜױၖവဳሦԥ࢙ෳ MOSFET ߹െă ߷ᆊ࢙ࣜ־߆ሓഉਦLjᇘዮဏݘᆾ٫ૣӤၙؙᅢݽӫ MOSFET ᇀሿڪུޔ۶ཙوዮؙဧ٫ૣă MOSFET የ௧٫ଁ ਜߔኪࡳ࢙դූስLjᄜཛྷߔॎ٧ණූࣚو٫൛ ࠧ٫ݮြ֑ષအስ٫ଁăሦቸݽ౷ስۢූᇀ LX وණෙ ᅳ࿒ऩኪࡳोڰLjԌᄸ٫ଁ၂Ԍդූ EMIăཛྷဋׅ ሦቸስLj৹ཛྷ୧ޔߔᇜࣩქהޔખ RC የ௧٫ଁăჾ ࿒ཛྷၭᇗהݡખ RC ٫ଁԸืوԧኊǖ 1) ᅋქޔԒಹຳ་Ռફ LX ባ GND و٫ႅLjԌߗՖ ስ౷ଔ fR Ǘ 2) ሖفქޔ৹टስ౷ଔऩّქҙو٫൛(٫൛ઘेᇀ LX ࠧ GND ቐࣺ)ă ்ଡ଼LjLX ණූࣚو٫൛(CPAR)টٌᅢණะ٫൛ و1/3ă ٫ଁූࣚو٫(ݮLPAR)Ѣ࿒ࣜǖ LPAR = 1 (2π fR ) 2 × CPAR ૅज़የ௧٫የ(RSNUB)ٌᅢ 2π x fR x LPARă৹ණ࿒ٻሿݡ ٫የჾࢩهୄᄌوየ௧ࣆܥ٫ႅ౭ჰăۚ٫൛(CSNUB)ᇘ ባඵᄮཛྷ C PAR و2 ባ 4 ӂ۽ԯᅘပăየ௧٫ଁࠞޢو (PRSNUB)ኙეᅑ٫የ RSNUB ࠞൾLj৹Ѣ࿒ࣜǖ PRSNUB = CSNUB × (VIN ) × fS 2 ದቲ VGS~VINă ׅණะຈࠞ༶Ljࡱᄮཛྷದດຈࠞૠؙ־ᆢ 20% ڪېوLj ದቲҪਸ਼ᅑᅢ MOSFET พ־٫൛ࣆ N2 ۠ࣁߘ۴ဂࢎݒ ٫ࠣᇀ N1 ቲຑᇒ֑وຈࠞLjሦቸຈࠞ෯،ᇀLjدᇀ ದቲ VIN ཛྷพ൩٫ႅLjfS ཛྷߔ౷ଔăѢሙ໎ڊᄮᅋຑე ഓوऩڪܹېLjცযණะࣜຑࠞޢهၭᇗ R SNUB ޢ ଔቚӶă ______________________________________________________________________________________ www.BDTIC.com/maxim 13 MAX1954A ڶᅢࠩوെߘහࣜLjӤၙᇀᆊಜوዮޠؙዷॕུ T J(MAX)࿒ࣜࠞޢăᅑᅢ٫ଁޠوዷ۽Lj N1 ࠧ N2 ᅘԥༀوຈ֑ࠞܖă N2 ޠዷᅢ٫ႅߔLj߆ದኙე ຈ ࠞ ก ـ ב ل ޱຈ ࠞ (PN2CC)ჾ ࣆ ۠ ࣁ ߘ ـ בຈ ࠞ (PN2DC)ă MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ พ൩٫൛ พ൩କԒ٫൛৹ऋඵ٫ᆚܥو־٫ૣLjԌऩّ ᅑ٫ଁߔۚᇀพ൩ණຑդූوᇑࣆ٫ႅླྀԒăพ൩ ٫൛Ӥၙୄዣᅑߔ٫ૣຑդූླྀوԒ٫ૣეഓ (IRMS)Lj Ѣ࿒ࣜǖ IRMS = ILOAD × ( VOUT × VIN − VOUT ) VIN ದቲLjصพ൩٫ႅٌᅢӂพ־٫ႅ෫(VIN = 2 x VOUT)Lj IRMS ዮؙLj߆ IRMS(MAX) = ILOAD / 2ăजᄓԳᅋ໋ׯ٫ ൛Ljᄜཛྷ໋ׯ٫൛ᇀݽ౷ණᅘृٌّوပהખ٫የ (ESR)ࣆٌပהખ٫(ݮESL)LjೲದڶӔृӯჵă৹ၭᇗ ქቸᇀዮؙো( ޗ۽RMS) ޠዷ٫ૣ࿒ུෙԥմ߹ 10°C و ٫൛Ljჾࢩهዮࣧوլಜ৹৯၂ă พ־٫൛ พ־٫൛ߔوऒԸืၭᇗཛྷǖ෯࣠٫൛ĂESRĂESL ࣆ ٫ႅቚӶეഓăሦဗԸืᄸሿེڊ၂Ăพ־٫ႅླྀ Ԓࣆ๊ຢᄮăพླྀ־Ԓوြ֑ᅘൻޔᄜǖ،ᇀพ ־٫൛ቲو٫ࠣوӰࡧĂᅑ६־٫൛و٫ૣᇀ٫൛ وESR ࣆ ESL ණຑդූوႅऩăዮླؙྀԒ٫ႅ৹Ѣ࿒ǖ VRIPPLE = VRIPPLE(ESR) + VRIPPLE(C) + VRIPPLE(ESL) ᅑ ESRĂพ־٫൛ࣆ ESL ຑդූوพ־٫ႅླྀԒܖӼࣜ ࿒ǖ VRIPPLE(ESR) = IP−P × ESR VRIPPLE(C) = IP−P 8 × COUT × fS ⎛V ⎞ VRIPPLE(ESL) = ⎜ IN ⎟ × ESL ⎝ L ⎠ ⎛V − V ⎞ ⎛V ⎞ OUT OUT IP−P = ⎜ IN ⎟ × ⎜ ⎟ fS × L ⎠ ⎝ VIN ⎠ ⎝ 14 ದቲ IP-P ཛྷܥ-ܥ٫ݮ٫ૣ(Ըऑ٫ݮԩ)ܖăሦဗ֔۽४ คࠩᅢၭᇗֽ٫൛LjዮቷᇘᄮѢሙᆓျࢪಂ٫ ଁੂ६ှၭᇗăዷཛྷქቸಗӵคᅋوᆓᇘLjृဏو٫ૣ ླྀԒդූृّوพ־٫ႅླྀԒLjᄜཛྷ٫ླྀݮԒ٫ૣཛྷ٫ ݮࣆพ൩٫ႅืࠉوLjᄜױLjพ־٫ႅླྀԒ٫ࣆݮ พ൩٫ႅوᇜࣩۚऋඵăڶᅢ MAX1954A LjजᄓԳᅋভ ࠩྡĂ᭕ࢪଋ٫ॖ٫൛ă߷ेถृ؍֧ྡوؙLj ᄊ৹ෳᅋ ESR وّृڶચࣱଋ٫ॖ٫൛ăཛྷവү৹ ৯ĂѠഩޠوዷLjᄮүቆ٫൛ႅࣆླྀԒ٫ૣڊېቚӶ մ߹ࣜă ಹऔݘڶᆾ๊Ӱوᄮടৈᅢຑၭᇗوพ־٫൛ă իLjพ־٫൛ وESR ᆣဏLj๊ຢᄮ໎၂ᆣࠝăۢූ ݘᆾ๊ӰࡍLjพ־٫ႅ࢙࣊ݢӰǖ ESR x ΔI LOADăᇀ ਈቨಹዶ־۴ᄮቐLjพ־٫ႅट६ქԧ౭ჰLjട ৈᅢ٫ݮĂพ־٫൛ؙوဏăॿ߹ქوڮृޔ෫ࣺࡍ(Ը ৬٨ျޠዷ໎၂ )Ljਈቨಹዶ־ᄮLj߹ٻॎพ־٫ႅ ۴ਯटದེڊᇀӶ֎٫ႅăਈቨಹوᄮ෫ࣺᅑӡ؞ ਝৈڊLj౷؞ᆣਝLjᄮᆣਜLjየቛพ־٫ႅ६ქ ԧ౭ེႅă ԣխහࣜ MAX1954A Գᅋქޔԩਗྥـؙ܅ಹLjದพ־ᅋੂ ԣխਈቨଁă༶ԩ٫ݮĂݽӫ MOSFET Ăพ־٫൛Ă ԣխ٫የࣆԣխ٫൛ٌৈڊષଁڊེو၂ă٫ࣆݮพ ־٫൛৹ޗয၂Ă֧֑ࣆ؍ӊੂၭᇗăၭᇗคوصԣ խ٫የࣆ٫൛৹ᅍࡧਈቨଁڊེو၂ă༐ 1 ࣆ༐ 2 ቲو ᆐऔ৹ᇀوڊޖพ൩٫ႅĂพ־٫ႅჾࣆݘᆾ٫ૣ۶ ཙࢩޠوڊེهዷăਈቨಹԳᅋ٫ૣனਈቨ۽ѦLj ሦቸ۽Ѧ߹ٻਈૣ߹٫وݮ٫ૣੂٻሿพ־٫ႅă MAX1954A ઉᅋݽӫ MOSFET ـو٫የ(RDS(ON))ණو ႅऩੂंՌ٫ݮ٫ૣă٫ૣனਈቨ۽Ѧဋׅષ۴ਯ ଁቲᅑ٫ࣆݮพ־٫൛դූوใࣁ٧LjჰޚဏLjྐၖ ྥڶؙ܅ಹዷॽ࿈وԣխăቝၖᅋქהޔખԣխ٫የ (RC)ࣆ٫൛(CC)Lj࣊৹ᇀᅋ໋ׯ٫൛ዷพ־କԒوᄮᅋቲ ࢩوڊེهਝଁ؞ăڶᅢದຓ੮ျو٫൛Ljᅑᅢದ٫ ൛ࣆ ESR ृݽLj߆ᅑ٫൛ࣆ ESR ຑդූو٧౷ଔّᅢ ᆊಜوӡयᆣ౷ଔLjᄜױၖეᇜࣩ༶ქޔԣխ٫൛ ੂّဋሦޔ٧ă ______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ GMOD = gmc × RLOAD × fS × L RLOAD + fS × L ದቲ R LOAD = V OUT / I OUT(MAX) Ljೲ g mc = 1 / (A CS x RDS(ON))Ljሦ ACS ཛྷ٫ૣंՌؙ܅ಹᇜᄐLjRDS(ON)ཛྷݽ ӫ MOSFET ـو٫የLjೲ ACS ٌᅢ 3.5ăᅑޢଔٻቨಹ դූࣁو٧ࣆ٧౷ଔѢ࿒ࣜǖ 1 fpMOD = ⎛R ⎞ × fS × L 2π × COUT × ⎜ LOAD + RESR ⎟ ⎠ ⎝ RLOAD + fS × L fzMOD = 1 2π × COUT × RESR ۴ਯܖႅಹᅘᇜᄐ G FB = V FB / V OUT Ljದቲ V FB ٌᅢ 0.8V ăਗྥـؙ܅ಹᅘቓૣᇜᄐ G EA(DC) = g m x ROăؙ܅ಹพ־٫የ٨ျཛྷ 10MΩăCCĂRO ࣆ RC വڊ ષქޔኙࣁ٧LjRC ࣆ CC വڊષქޔ٧ăᅑ CF ࣆ RC വ وڊქޔ৹ၭࣁ٧Ljဋׅพ־٫൛ ESR ٧ĊĊ߷ດۢ ූᇀयᆣ౷ଔ(fC)ቐࡨوǖ fpdEA = 1 2 π × CC × (RO + RC ) 1 fzEA = 2π × C C × R C 1 fpEA = 2π × C F × R C fC ᄮᆜᆜݽᅢޢଔٻቨಹࣁو٧౷ଔ fPMODLjೲयᆣ౷ଔ ᄮّᅢ 1/8 ߔ౷ଔǖ fpMOD << fC < MAX1954A ࢱӊེوႅಹଁ৹ӇዷქޢޔଔٻቨಹĂพ־۴ਯ ܖႅಹࣆྥؙ܅ಹăޢଔٻቨಹᅘቓૣᇜᄐ g mc x RLOADLjԌᅘქޔᅑ RLOADĂพ־٫൛(COUT)ࣆದٌပ הખ٫የ (RESR)വ ࣁوڊ-٧ۛڶăჾ࿒ཛྷڊᄏޢଔٻ ቨಹާوǖ fS 8 ᄜױLjयᆣ౷ଔ࿒ଁوᇜᄐࣜާཛྷǖ GEA(fC) × GMOD(fC) × VFB =1 VOUT صfzMOD ؙᅢ fC ෫Ljᅘǖ GEA(fC) = gmEA × RC and GMOD(fC) = gmc × RLOAD × fpMOD fC ᇘ RC ࣜ࿒ǖ RC = VOUT gmEA × VFB × GMOD(fC) ದቲ gmEA = 110μsă ᅑ RC ࣆ CC ြ֑ྥوؙ܅ಹԣխ٧ᄮӇහብᇀٻቨಹ ࣁ٧ fpMOD ණLjCC Ѣ࿒ࣜǖ R × fS × L × COUT CC = LOAD (RLOAD + (fS × L)) × RC ߷ fzMOD ဏᅢ 5 x fCLjᇘᇀ COMP ᅳ GND ቐࣺᇜࣩٞ۠ ޔԣխ٫൛ Cf ੂّဋ ESR ٧ăCf ࣜ࿒ǖ Cf = 1 2π × RC × fzMOD ዅݘᆾ٫ૣوऋඵLjٻቨಹࣁ٧ნᄮऩّăٻدቨ ಹᇜᄐല࢙ᇜࣩLjᄜۚयᆣ౷ଔү֞ԥӰă صfzMOD ဏᅢ fC ෫LjfC ࿒ޢوଔٻቨಹᇜᄐཛྷǖ GMOD(fC) = GMOD(DC) × fpMOD fzMOD ______________________________________________________________________________________ www.BDTIC.com/maxim 15 MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ fC ࿒ྥوؙ܅ಹᇜᄐཛྷǖ f GEA(fC) = gmEA × RC × zMOD fC RC ࣜ࿒ǖ V fC RC = OUT × VFB gmEA × fzMOD × GMOD(fC) CC ࣆ Cf ࣜ࿒ǖ R × fS × L × COUT CC = LOAD (RLOAD + fS × L) × RC Cf = 1) ट IC ണᱺ٫൛ॳ৹ٜ৯॰ IC ᄧहLjԌटޢଔٜ౿ எ ( ᅳᄧह 7 ઘे ) ᅳဳٜࠟ౿எ ( ᅳᄧह 4 ઘे ) ܖă IN ᄧहᅘޔണᱺ٫൛LjܖӼᅳᄧह 7 ࣆ 4 ઘेă 2) ट MOSFET ണᱺ٫൛ॳ৹ٜ৯॰ĂԌቓेटದਗे ᇀݽӫ MOSFET ࣁᅳّӫ MOSFET ᆚࣁණă 3) टพ൩ࣆพ־٫൛ेޢفଔٜ౿எණLjຑᅘದຓ٫൛ ᅳဳٜࠟ౿எઘेă 4) ؙ٫ૣॳل৹ڮă 5) टޢଔ MOSFET ࣁوᄧᅳؙஎࢵ༁பઘेੂҝኜ ಹऔൾെăԸ৬ޢଔ MOSFET ืযዊቲᅘߔܳ༁எ ࢵوजᄓă 6) ट HSD ቓेᅳݽӫ MOSFET ࣁوઘेă 7) ट LX ቓेᅳّӫ MOSFET ࣁوઘेă VOUT 2π × RC × fzMOD 8) ෳّӫ MOSFET وᆚࣁॳ৹৯॰ᄧह 7ă ________________________________ ᄮᅋဳྲ 9) വүຑᅘ۴ਯઘेۚڮቓLjट۴ਯ٫የॳ৹৯॰ ICă ӹ 2 ઼־ષქဗ༚ऌᅳ MAX1954A ైࠩෳᅋوಹऔቨ ᇒඨă 10) Ԧ෫ᄮෳݽߔॎ٧ᆜஜوݮன௨ഘᅺ (FB, COMP)ă PCB Ԧনቚـ 11) ّӫࣆݽӫ MOSFET ᇨࣁ فDH ࣆ DL وዟլڪԥ ეմ߹ 700milă ॽဲ وPCB Ԧনڶᅢ෯ّߔຈࠞࣆེޠوڊዷ܇ի ߔऒLjߔޢଔ࣌ᅐದၖე໎Ӽဏဲă৹Ը৬ჾ࿒ቚـ ६ှનࠝ وPCB Ԧনǖ ཛྷҝኜහࣜLjMAX1954A ಂғ໗ޥષქޔԦন۶ઋă ӹ 2. ༚ऌկඨ MANUFACTURER Central Semiconductor COMPONENT PHONE WEBSITE Diodes 631-435-1110 www.centralsemi.com Coilcraft Inductors 800-322-2645 www.coilcraft.com Fairchild MOSFETs 800-341-0392 www.fairchildsemi.com Kemet Capacitors 864-963-6300 www.kemet.com Panasonic Capacitors 714-373-7366 www.panasonic.com Taiyo Yuden Capacitors 408-573-4150 www.t-yuden.com Inductors 800-745-8656 www.toko.com TOKO 16 ______________________________________________________________________________________ www.BDTIC.com/maxim ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ ____________________________ ာ౮ဳྲ TRANSISTOR COUNT: 2963 PROCESS: BiCMOS VIN 3V TO 5.5V IN VHSD 5.5V TO 13.2V HSD BST DH N MAX1954A LX VOUT 0.8V TO 0.93 VIN COMP DL N PGND GND FB ______________________________________________________________________________________ www.BDTIC.com/maxim 17 MAX1954A _________________________٨ျޠዷ٫ଁ ___________________________________________________________________ ܢኰဳྲ (ӊืযዊ໗ܢوޥኰ༐৹ԥกዮ॰ޏߢوLjၖዮ॰ܢوኰ༶ြဳྲLjഋՓၻ www.maxim-ic.com.cn/packagesă) e 10LUMAX.EPS MAX1954A ّ֑ӊĂ٫ૣன PWM buck ਈቨಹLj ؞ሟ۵٫ૣቨ 4X S 10 INCHES 10 H Ø0.50±0.1 0.6±0.1 1 1 0.6±0.1 BOTTOM VIEW TOP VIEW D2 MILLIMETERS MAX DIM MIN 0.043 A A1 0.002 0.006 A2 0.030 0.037 D1 0.116 0.120 D2 0.114 0.118 E1 0.116 0.120 E2 0.114 0.118 H 0.187 0.199 L 0.0157 0.0275 L1 0.037 REF b 0.007 0.0106 e 0.0197 BSC c 0.0035 0.0078 0.0196 REF S α 0° 6° MAX MIN 1.10 0.05 0.15 0.75 0.95 2.95 3.05 2.89 3.00 2.95 3.05 2.89 3.00 4.75 5.05 0.40 0.70 0.940 REF 0.177 0.270 0.500 BSC 0.090 0.200 0.498 REF 0° 6° E2 GAGE PLANE A2 c A b D1 A1 E1 α L L1 FRONT VIEW SIDE VIEW PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE, 10L uMAX/uSOP APPROVAL DOCUMENT CONTROL NO. 21-0061 REV. 1 1 Nbyjn ۱யࠀူێ ۱ய 9439ቧረ ᎆᑶܠ൩ 211194 ॅ࢟જǖ911!921!1421 ࢟જǖ121.7322 62:: ࠅᑞǖ121.7322 63:: Nbyjn࣪ݙNbyjnޘອጲᅪࡼྀੜ࢟വဧঌᐊLjጐݙᄋᓜಽభăNbyjnۣഔᏴྀੜဟମĂᎌྀੜᄰۨࡼ༄ᄋሆኀখޘອᓾ೯ਜ਼ਖৃࡼཚಽă 18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Printed USA ဵ Nbyjn!Joufhsbufe!Qspevdut-!Jod/ ࡼᓖݿܪă www.BDTIC.com/maxim