LT3782A LINER [Linear Technology], LT3782A Datasheet
LT3782A
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LT3782A Summary of contents
Page 1
... The LT3782A is identical to the LT3782 except that the LT3782A has a tighter current sense mismatch tolerance. The LT3782A is available in thermally enhanced 28-lead TSSOP and 4mm × 5mm QFN packages. ...
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... LT3782AIFE LT3782AIFE#TR LT3782AEUFD LT3782AEUFD#TR LT3782AIUFD LT3782AIUFD#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ...
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... SET R = 40k SET R = 80k SET – 25mV, R > 80k FB REF SET R = 40k SET R = 80k, V ≤ 0.3V SET DCL V = 1.2V DCL DCL RSET V ≤ 0.3V DCL LT3782A MIN TYP MAX ≤ 40V 2.3 2.45 2.6 80 0.4 0. –0.5 –2 2.42 2.44 2.464 l 2.4 2.488 l 200 260 370 l 0 ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LT3782AE is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls ...
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... G06 120 110 100 400 500 600 3782A G08 LT3782A T = 25°C, unless otherwise noted. A Current Limit Threshold vs Temperature –45 – 150 TEMPERATURE (°C) 3782A G05 SGATE (Low) to BGATE (High) ...
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... PWM. Switching starts at 0.7V, and higher V corresponds to higher inductor current. FB (Pin 16/Pin 13): Error Amplifi er Inverting Input. A resistor divider to this pin sets the output voltage. RUN (Pin 17/Pin 14): LT3782A goes into shutdown mode when V RUN shutdown mode when V V (Pin 19/Pin 16): Gate Driver BGATE2 Ground ...
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... CL1 – + 60mV + 2.5V BGATE2 A18 SLOPE COMP CH2 + CH2 PWM2 – A10 + CL2 – 60mV 2000pF LT3782A L1 D1 15μH L2 GBIAS1 15μ GBIAS2 C3 A8 2μF 21 – + GBIAS 28 V – 2.5V CC SGATE1 A1 2 DELAY ONE SHOT 6 R SET GBIAS1 BGATE1 ...
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... RUN pin to set the desired V undervoltage lockout voltage. 80mV of hysteresis is built in on RUN pin thresholds. to turn C Oscillation Frequency Setting and Synchronization The switching frequency of LT3782A can be set up to 500kHz by a resistor R For f = 250kHz, R SET Once the switching frequency f found from the Switching Frequency vs R under the Typical Performance Characteristics section ...
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... For high output voltage applications, the power loss of the catch diodes are relatively small because of high duty cycle. If diodes power loss or heat is a concern, the LT3782A provides PWM signals through SGATE1 and SGATE2 pins to drive external MOSFET drivers for synchronous recti- fi ...
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... When DCL pin is shorted to R pin and switching fre- SET quency is less than 250kHz (R FREQ duty cycle of LT3782A will be at least 90%. The maximum duty cycle can be clamped to 50% by grounding the DCL pin or to 75% by forcing the V DCL resistor divider from R pin to ground. The typical DCL SET pin input current is 0.2μ ...
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... APPLICATIONS INFORMATION The Peak and Average Input Currents The control circuit in the LT3782A measures the input cur- rent by using a sense resistor in each MOSFET source, so the output current needs to be refl ected back to the input in order to dimension the power MOSFET properly. Based ...
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... LT3782A APPLICATIONS INFORMATION The gate drive voltage is set by the 10V GBIAS regulator. Consequently, 10V rated MOSFETs are required in most high voltage LT3782A applications. Pay close attention to the BV DSS MOSFETs relative to the maximum actual switch voltage in the application. The switch node can ring during the turn-off of the MOSFET due to layout parasitics ...
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... Thus the 2-phase technique signifi cantly reduces the output capacitor size. 2-PHASE 0.8 1.0 3782A F05 Figure 6. Normalized Output RMS Ripple Currents in Boost Converter: 1-Phase and 2-Phase. I LT3782A • 3.25 3.00 2.75 2.50 2.25 2 ...
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... Although all dissipative elements in the circuit produce losses, four main sources usually account for the majority of the losses in LT3782A application circuits: 1. The supply current into V of the DC supply current I acteristics) and the MOSFET driver and control currents. ...
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... IN inductor core losses, generally account for less than 2% of the total losses. PCB Layout Considerations To achieve best performance from an LT3782A circuit, the PC board layout must be carefully done. For lower power applications, a two-layer PC board is suffi cient. However, MAX at higher power levels, a multiplayer PC board is recom- mended ...
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... SENSE2 10nF 10Ω CS2 SENSE2 14 SS 4.7nF 16 10V to 24V Input to 24V, 8A Output Boost Converter 10V TO 24V INPUT 28 GBIAS 2R2 1μ LT3782A 24 V EE1 23 BGATE1 22 GBIAS1 21 GBIAS2 2.2μF 20 BGATE2 19 V EE2 825k 18 NC 274k 17 RUN 24. 221k ...
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... TYPICAL APPLICATIONS LT3782A 3782af 17 ...
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... LT3782A PACKAGE DESCRIPTION 4.75 (.187) 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN MILLIMETERS (INCHES) 3. DRAWING NOT TO SCALE 18 FE Package 28-Lead Plastic TSSOP (4.4mm) ...
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... UFD Package 28-Lead Plastic QFN (4mm × 5mm) (Reference LTC DWG # 05-08-1712 Rev B) 0.70 ±0.05 3.65 ± 0.05 PACKAGE OUTLINE 3.50 REF 4.10 ± 0.05 5.50 ± 0.05 0.75 ± 0.05 4.00 ± 0.10 (2 SIDES) 0.200 REF 0.00 – 0.05 LT3782A PIN 1 NOTCH 2.50 REF R = 0. 0.115 × 45° CHAMFER TYP TYP 3.50 REF 3.65 ± ...
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... 30V IN 60A to 240A Output Current, 0.6V ≤ V Pin Compatible with LT3782A Adjustable Slope Compensation, Internal Soft-Start High Effi ciency, Improves Cross Regulation in Multiple Output Designs, Current Mode, 3mm × 4mm 12-Pin DFN Package 30V, 99% Duty Cycle, 4mm × 4mm QFN, 4mm × 5mm QFN and ...