LTC3862EFE#PBF Linear Technology, LTC3862EFE#PBF Datasheet
LTC3862EFE#PBF
Specifications of LTC3862EFE#PBF
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LTC3862EFE#PBF Summary of contents
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... L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 6144194, 6498466, 6611131. ...
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... SENSE2 PLLFLTR FE PACKAGE 24-LEAD PLASTIC TSSOP = 150°C, θ 38°C/W JMAX JA EXPOSED PAD (PIN 25) IS PGND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3862EFE#PBF LTC3862EFE#TRPBF LTC3862IFE#PBF LTC3862IFE#TRPBF LTC3862HFE#PBF LTC3862HFE#TRPBF LTC3862EGN#PBF LTC3862EGN#TRPBF LTC3862IGN#PBF LTC3862IGN#TRPBF LTC3862HGN#PBF LTC3862HGN#TRPBF LTC3862EUH#PBF LTC3862EUH#TRPBF ...
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ELECTRICAL CHARACTERISTICS operating junction temperature range, otherwise specifi cations are at T otherwise noted. SYMBOL PARAMETER Supply Input and INTV Linear Regulator Supply Voltage Range Supply Current VIN IN Normal Mode, No Switching ...
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LTC3862 ELECTRICAL CHARACTERISTICS operating junction temperature range, otherwise specifi cations are at T otherwise noted. SYMBOL PARAMETER f SYNC Minimum Input Frequency SYNC SYNC Maximum Input Frequency V SYNC Input Threshold SYNC I Phase Detector Sourcing Output Current PLLFLTR Phase ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Output Current 100 V = 48V OUT 35V 24V 12V 100 LOAD CURRENT (mA) ...
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LTC3862 TYPICAL PERFORMANCE CHARACTERISTICS INTV Line Regulation CC 5.25 5.00 4. INPUT VOLTAGE (V) 3962 G09 INTV LDO Dropout vs Load CC Current, Temperature 1600 1400 150°C 1200 125°C 1000 85°C 800 25°C 600 –40°C ...
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TYPICAL PERFORMANCE CHARACTERISTICS Maximum Current Sense Threshold vs Duty Cycle 80 SLOPE = 0.625 75 70 SLOPE = 1 SLOPE = 1. DUTY CYCLE (%) 3862 ...
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LTC3862 TYPICAL PERFORMANCE CHARACTERISTICS Oscillator Frequency vs Input Voltage 320 315 310 305 300 295 290 285 280 INPUT VOLTAGE (V) 3862 G27 Frequency Voltage vs Temperature 1.235 1.233 1.231 1.229 ...
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PIN FUNCTIONS 3V8: Output of the Internal 3.8V LDO from INTV pin for the low voltage analog and digital circuits. A low ESR 1nF ceramic bypass capacitor should be connected between 3V8 and SGND, as close as possible to the ...
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LTC3862 PIN FUNCTIONS + + SENSE1 , SENSE2 : Positive Inputs to the Current Comparators. The ITH pin voltage programs the current comparator offset in order to set the peak current trip threshold. This pin is normally connected to a ...
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FUNCTIONAL DIAGRAM CLKOUT SYNC PLLFLTR MAX PHASEMODE FREQ R FREQ SLOPE SLOPE COMPENSATION BLANK BLANK BLOGIC LOGIC 3V8 5μ ITH PSKIP PSKIP – + 0.275V ...
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LTC3862 OPERATION The Control Loop The LTC3862 uses a constant frequency, peak current mode step-up architecture with its two channels operat- ing 180 degrees out of phase. During normal operation, each external MOSFET is turned on when the clock for ...
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OPERATION In multi-phase applications, all of the FB pins are connected together and all of the error amplifi er output pins (ITH) are connected together. The INTV pins, however, should not CC be connected together. The INTV CC sourcing current ...
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LTC3862 OPERATION To prevent the maximum junction temperature from be- ing exceeded, the input supply current to the IC should be checked when operating in continuous mode (heavy load) at maximum tradeoff between the operating IN frequency ...
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OPERATION Operation at High Supply Voltage At high input voltages, the LTC3862’s internal LDO can dissipate a signifi cant amount of power, which could cause the maximum junction temperature to be exceeded. Conditions such as a high operating frequency, or ...
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LTC3862 OPERATION Operation of the RUN Pin The control circuitry in the LTC3862 is turned on and off using the RUN pin. Pulling the RUN pin below 1.22V forces shutdown mode and releasing it allows a 0.5μA current source to ...
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OPERATION The LTC3862 uses a constant frequency architecture that can be programmed over a 75kHz to 500kHz range using a single resistor from the FREQ pin to ground. Figure 6 illustrates the relationship between the FREQ pin resistance and the ...
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LTC3862 OPERATION Table 1 CH-1 to CH-2 CH-1 to CLKOUT PHASEMODE PHASE PHASE SGND 180° 90° Float 180° 60° 3V8 120° 240° Using the LTC3862 Transconductance (g Amplifi Multi-Phase Applications The LTC3862 error amplifi transconductance, ...
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OPERATION LTC3862 chip, connect all of the SS pins together and use one external capacitor to program the soft-start time. In this case, the current into the soft-start capacitor will • 5μA, where n is the ...
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LTC3862 OPERATION the slope compensation is too low the converter can suffer from excessive jitter or, worst case, sub-harmonic oscillation. When excess slope compensation is applied to the internal current sense signal, the phase margin of the control loop suffers. ...
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OPERATION MINIMUM ON-TIME AT LIGHT LOAD WITH BLANK = SGND INDUCTOR CURRENT 1A/DIV GATE 2V/DIV SW NODE 20V/DIV V = 30V 200ns/DIV 48V OUT MEASURED ON-TIME = 180ns MINIMUM ON-TIME AT LIGHT LOAD WITH BLANK = FLOAT ...
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LTC3862 OPERATION + – The SENSE and SENSE Pins + – The SENSE and SENSE pins are high impedance inputs to the CMOS current comparators for each channel. Nominally, there current into or out of these pins. ...
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OPERATION The ITH series R • C fi lter sets the dominant pole-zero C C loop compensation. The transfer function for boost and fl yback converters contains a right half plane zero that normally requires the loop crossover frequency to ...
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LTC3862 APPLICATIONS INFORMATION Typical Boost Applications Circuit A basic 2-phase, single output LTC3862 application circuit is shown in Figure 18. External component selection is driven by the characteristics of the load and the input supply. Duty Cycle Considerations For a ...
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APPLICATIONS INFORMATION Maximum Duty Cycle Limitations Another operating extreme occurs at high duty cycle, when the input voltage is low and the output voltage is high. In this case: ⎛ ⎞ – MIN ...
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LTC3862 APPLICATIONS INFORMATION The inductor saturation current rating needs to be higher than the worst-case peak inductor current during an overload condition the maximum rated load O(MAX) current, then the maximum current limit value (I would normally ...
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APPLICATIONS INFORMATION result, some iterative calculation is normally required to determine a reasonably accurate value. The power dissipated by the MOSFET in a multi-phase boost converter with n phases is: 2 ⎛ ⎞ MAX ( ) = ⎜ ...
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LTC3862 APPLICATIONS INFORMATION For a boost converter where the current limit value is chosen to be 30% higher than the maximum load current, the peak current in the MOSFET and sense resistor is: ⎛ ...
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APPLICATIONS INFORMATION additional power dissipation is important when deciding on a diode current rating, package type, and method of heat sinking close approximation, the power dissipated by the diode is • V • (1 – ...
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LTC3862 APPLICATIONS INFORMATION For the bulk capacitance, which we assume contributes 1% to the total output ripple, the minimum required ca- pacitance is approximately MAX ( ) ≥ C OUT • • • ...
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APPLICATIONS INFORMATION The value of the input capacitor is a function of the source impedance, and in general, the higher the source impedance, the higher the required input capacitance. The required amount of input capacitance is also greatly affected by ...
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LTC3862 APPLICATIONS INFORMATION D MAX SLOPE BLANK PHASEMODE 45.3k FREQ 10nF SS 4.7nF LTC3862 30.1k ITH 100pF FB 12.4k SGND 475k V OUT CLKOUT SYNC PLLFLTR Figure 25a 36V Input, 48V/5A Output 2-Phase Boost Converter Application Circuit ...
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APPLICATIONS INFORMATION The inductor value chosen was 18.7μH and the part number is PB2020-223, manufactured by Pulse Engi- neering. This inductor has a saturation current rating of 20A. 8. The power MOSFET chosen for this application is a Renesas HAT2266H. ...
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LTC3862 APPLICATIONS INFORMATION For the bulk capacitance, which we assume contributes 1% to the total output ripple, the minimum required capacitance is approximately MAX ( ) ≥ OUT • • • ...
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APPLICATIONS INFORMATION 10. The output resistor divider should be located as close as possible to the IC, with the bottom resistor connected between FB and SGND. The PCB trace connecting the top resistor to the upper terminal of the output ...
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LTC3862 TYPICAL APPLICATIONS A 12V Input, 24V/5A Output 2-Phase Boost Converter Application Circuit D MAX SLOPE BLANK PHASEMODE 45.3k FREQ 10nF SS 1nF LTC3862 26.7k ITH 100pF FB 6.98k SGND 130k V OUT CLKOUT SYNC PLLFLTR Start-Up RUN 5V/DIV I ...
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TYPICAL APPLICATIONS A 4.5V to 5.5V Input, 12V/15A Output 4-Phase Boost Converter Application Circuit 45.3k 10nF 10nF 3.83k 330pF 18.7k 165k V OUT 45.3k 330pF 10nF 10k Start- 5V/DIV I MASTER L1 5A/DIV I MASTER L2 5A/DIV I ...
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LTC3862 PACKAGE DESCRIPTION 6.60 0.10 4.50 0.10 RECOMMENDED SOLDER PAD LAYOUT (.169 – .177) 0.09 – 0.20 (.0035 – .0079) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE .254 MIN .0165 .0015 RECOMMENDED SOLDER ...
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... ON THE TOP AND BOTTOM OF PACKAGE Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. UH Package 24-Lead Plastic QFN (5mm × ...
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... Constant Frequency Current Mode SENSE LTC3873-5 Flyback, Boost and SEPIC DC/DC Controllers LTC3780 High Effi ciency, Synchronous, 4-Switch Buck-Boost Controller PolyPhase is a registrated treademark of Linear Technology Corporation Linear Technology Corporation 40 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...