POWER LOSS (W) LT3782 2-Phase Step-UP NOT RECOMMENDED FOR NEW DESIGNS DC/DC Controller Contact Linear Technology for Potential Replacement FEATURES DESCRIPTION n 2-Phase Operation Reduces Required Input and The LT 3782 is a current mode two phase step-up DC/DC Output Capacitance converter controller. Its high switching frequency (up to n Programmable Switching Frequency: 500kHz) and 2-phase operation reduce system ltering 150kHz to 500kHz capacitance and inductance requirements. n 6V to 40V Input Range With 10V gate drive (V 13V) and 4A peak drive current, CC n 10V Gate Drive with V 13V CC the LT3782 can drive most industrial grade high power n High Current Gate Drive (4A) MOSFETs with high ef ciency. For synchronous applica- n Programmable Soft-Start and Current Limit tions, the LT3782 provides synchronous gate signals with n Programmable Slope Compensation for programmable falling edge delay to avoid cross conduc- High Noise Immunity tion when using external MOSFET drivers. Other features n MOSFET Gate Signals with Programmable include programmable undervoltage lockout, soft-start, Falling Edge Delay for External Synchronous current limit, duty cycle clamp (50% or higher) and slope Drivers compensation. n Programmable Undervoltage Lockout n The LT3782 is available in thermally enhanced 28-lead Programmable Duty Cycle Clamp (50% or Higher) n TSSOP and 4mm 5mm QFN packages. Thermally Enhanced 28-Lead TSSOP and 4mm 5mm QFN Packages For new designs use the LT3782A which has improved phase matching APPLICATIONS L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Industrial Equipment Protected by U.S. Patents including 6144194. n Telecom Infrastructure n Interleaved Isolated Power Supply TYPICAL APPLICATION 50V 4A Boost Converter V V IN OUT L1 10V TO 36V 50V, 4A D1 C OUT1 V GBIAS1 CC 10F Ef ciency and Power Loss 30BQ060 50V 1F R6 + L2 vs Load Current GBIAS2 C3 2x 825k D2 + 2F C 97 18 GBIAS OUT2 C 30BQ060 IN RUN M1 220F 10F V = 24V IN EFFICIENCY BGATE1 Si7852dp 50V R8 2x 95 15 274k 2x V = 12V IN R LT3782 S1 93 12 0.004 V R EE1 SLOPE V = 12V IN 59k M2 91 9 SLOPE BGATE2 Si7852dp 2x L1, L2: PB2020.223 DELAY V = 24V IN 89 6 C , C : X7R, TDK R IN OUT1 FREQ DCL R S2 80k POWER LOSS 0.004 R SET 87 3 V EE2 10 10 SS 85 0 + SENSE1 0.1F 0 1 2 3 4 5 10nF 10nF I (A) OUT SENSE1 R V F1 3782 TA01b C 475k + 13k SENSE2 100pF SENSE2 6.8nF R F2 FB GND 3782 TA01 24.9k 3782fg 1 EFFICIENCY (%)LT3782 ABSOLUTE MAXIMUM RATINGS (Note 1) V Supply Voltage ...................................................40V Storage Temperature Range ...................65C to 150C CC GBIAS, GBIAS1, GBIAS2 Pin Lead Temperature (Soldering, 10 sec) .................. 300C (Externally Forced) ....................................................14V SS ................................................................ 0.3V to 6V + + SYNC, RUN Pin .........................................................30V SENSE1 , SENSE2 , Operating Junction Temperature SENSE1 , SENSE2 ..................................... 0.3V to 2V Range (Notes 2, 3) ................................. 40C to 125C PIN CONFIGURATION TOP VIEW TOP VIEW 1 28 GBIAS SGATE2 2 27 V SGATE1 CC 3 26 NC NC 28 27 26 25 24 23 4 25 NC GND SYNC 1 22 BGATE1 5 24 V DELAY 2 21 GBIAS1 SYNC EE1 DCL 3 20 NC 6 BGATE1 DELAY 23 + SENSE1 4 19 NC 7 GBIAS1 DCL 22 29 29 + SENSE1 5 18 GBIAS2 8 GBIAS2 SENSE1 21 SLOPE 6 17 BGATE2 SENSE1 9 20 BGATE2 R 7 16 V SET EE2 SLOPE 10 19 V EE2 8 SENSE2 15 NC R 11 18 NC SET 9 10 11 12 13 14 SENSE2 12 17 RUN + SENSE2 13 16 FB SS 14 15 V C UFD PACKAGE 28-LEAD (4mm 5mm) PLASTIC QFN FE PACKAGE T = 125C, = 37C/ W 28-LEAD PLASTIC TSSOP JMAX JA EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB T = 125C, = 38C/ W JMAX JA EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT3782EFE PBF LT3782EFE TRPBF LT3782EFE 28-Lead Plastic TSSOP 40C to 85C LT3782IFE PBF LT3782IFE TRPBF LT3782IFE 28-Lead Plastic TSSOP 40C to 125C LT3782EUFD PBF LT3782EUFD TRPBF 3782 28-Lead (4mm 5mm) Plastic QFN 40C to 85C LEAD BASED FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LT3782EFE LT3782EFE TR LT3782EFE 28-Lead Plastic SSOP 40C to 85C LT3782IFE LT3782IFE TR LT3782IFE 28-Lead Plastic SSOP 40C to 125C LT3782EUFD LT3782EUFD TR 3782 40C to 85C 28-Lead (4mm 5mm) Plastic QFN Consult LTC Marketing for parts speci ed with wider operating temperature ranges. For more information on lead free part marking, go to: