数据表 (LM3429BSTEVAL/NOPB)目录Features1Applications1Description1Typical Boost Application Circuit1Connection Diagram2Absolute Maximum Ratings3Operating Conditions3Electrical Characteristics4Typical Performance Characteristics6Block Diagram8Theory of Operation8CURRENT REGULATORS9Buck9Boost9Buck-boost9PREDICTIVE OFF-TIME (PRO) CONTROL9SWITCHING FREQUENCY10Buck (Constant Ripple vs. VIN)11Buck (Constant Ripple vs. VO)11Boost and Buck-boost11AVERAGE LED CURRENT11ANALOG DIMMING12CURRENT SENSE/CURRENT LIMIT13CONTROL LOOP COMPENSATION14OUTPUT OVER-VOLTAGE LOCKOUT (OVLO)16Ground Referenced17Floating17INPUT UNDER-VOLTAGE LOCKOUT (UVLO)17UVLO only18PWM dimming and UVLO18PWM DIMMING18STARTUP REGULATOR (VCC LDO)19THERMAL SHUTDOWN19Design Considerations19INDUCTOR19LED DYNAMIC RESISTANCE (rD)20OUTPUT CAPACITOR20INPUT CAPACITORS20N-CHANNEL MosFET (NFET)21RE-CIRCULATING DIODE21CIRCUIT LAYOUT21Basic Topology Schematics22BOOST REGULATOR (VIN < VO)22BUCK REGULATOR (VIN > VO)23BUCK-BOOST REGULATOR23Design Guide24SPECIFICATIONS241. OPERATING POINT242. SWITCHING FREQUENCY243. AVERAGE LED CURRENT254. INDUCTOR RIPPLE CURRENT255. LED RIPPLE CURRENT266. PEAK CURRENT LIMIT267. LOOP COMPENSATION268. INPUT CAPACITANCE289. NFET2910. DIODE2911. OUTPUT OVLO3012. INPUT UVLO3013. PWM DIMMING METHOD3114. ANALOG DIMMING METHOD31Design Example #131BUCK-BOOST APPLICATION - 6 LEDs at 1A31SPECIFICATIONS321. OPERATING POINT322. SWITCHING FREQUENCY323. AVERAGE LED CURRENT334. INDUCTOR RIPPLE CURRENT335. OUTPUT CAPACITANCE336. PEAK CURRENT LIMIT347. LOOP COMPENSATION348. INPUT CAPACITANCE359. NFET3510. DIODE3611. INPUT UVLO3612. OUTPUT OVLO36Design #1 Bill of Materials37Applications Information38DESIGN #2: BOOST PWM DIMMING APPLICATION - 9 LEDs at 1A38Design #2 Bill of Materials38DESIGN #3: BUCK-BOOST ANALOG DIMMING APPLICATION - 4 LEDs at 2A39Design #3 Bill of Materials39DESIGN #4: BOOST ANALOG DIMMING APPLICATION - 12 LEDs at 700mA40Design #4 Bill of Materials40DESIGN #5: BUCK-BOOST PWM DIMMING APPLICATION - 6 LEDs at 500mA41Design #5 Bill of Materials41DESIGN #6: BUCK APPLICATION - 3 LEDS AT 1.25A42Design #6 Bill of Materials42DESIGN #7: BUCK-BOOST THERMAL FOLDBACK APPLICATION - 8 LEDs at 2.5A43Design #7 Bill of Materials43DESIGN #8: SEPIC APPLICATION - 5 LEDs at 750mA44Design #8 Bill of Materialslayout of National Data Sheet to TI format44Revision History45文件大小: 1.7 MB页数: 51Language: English打开用户手册