LTC3890EGN-1#TRPBF Linear Technology, LTC3890EGN-1#TRPBF Datasheet
LTC3890EGN-1#TRPBF
Specifications of LTC3890EGN-1#TRPBF
Related parts for LTC3890EGN-1#TRPBF
LTC3890EGN-1#TRPBF Summary of contents
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... PGOOD outputs, see the LTC3890 data sheet. L, LT, LTC, LTM, Linear Technology, Burst Mode, OPTI-LOOP and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620, 6100678, 6144194, 6177787, 6304066, 6580258, 7230497 ...
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... LTC3890H-1 ....................................... –40°C to 150°C LTC3890MP-1 .................................... –55°C to 150°C Storage Temperature Range .................. –65°C to 150°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3890EGN-1#PBF LTC3890EGN-1#TRPBF LTC3890IGN-1#PBF LTC3890IGN-1#TRPBF LTC3890HGN-1#PBF LTC3890HGN-1#TRPBF LTC3890MPGN-1#PBF LTC3890MPGN-1#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Input Supply Operating Voltage Range IN V Regulated Feedback Voltage FB1,2 I Feedback Current FB1,2 V Reference Voltage Line Regulation REFLNREG V Output Voltage Load Regulation LOADREG g ...
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LTC3890-1 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER TG/BG t Top Gate Off to Bottom Gate On Delay 1D Synchronous Switch-On Delay Time BG/TG t Bottom Gate Off to Top Gate On Delay 1D Top Switch-On ...
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TYPICAL PERFORMANCE CHARACTERISTICS Efficiency and Power Loss vs Output Current 100 V = 12V BURST EFFICIENCY 3.3V 90 OUT 80 70 CCM LOSS 60 50 BURST LOSS PULSE-SKIPPING 40 LOSS 30 CCM EFFICIENCY 20 PULSE-SKIPPING 10 EFFICIENCY ...
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LTC3890-1 TYPICAL PERFORMANCE CHARACTERISTICS Total Input Supply Current vs Input Voltage 300 V = 3.3V OUT FIGURE 13 CIRCUIT 250 200 300μA LOAD 150 100 NO LOAD ...
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TYPICAL PERFORMANCE CHARACTERISTICS TRACK/SS Pull-Up Current vs Temperature 1.10 1.05 1.00 0.95 0.90 –75 –50 – 100 125 150 TEMPERATURE (°C) 38901 G19 – SENSE Pin Total Input Bias Current vs Temperature 800 700 V > ...
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LTC3890-1 PIN FUNCTIONS ITH1, ITH2 (Pin 1, Pin 13): Error Amplifier Outputs and Switching Regulator Compensation Points. Each associ- ated channel’s current comparator trip point increases with this control voltage (Pin 2, Pin 12): Receives the remotely ...
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PIN FUNCTIONS BG1, BG2 (Pin 23, Pin 18): High Current Gate Drives for Bottom (Synchronous) N-Channel MOSFETs. Voltage swing at these pins is from ground to INTV BOOST1, BOOST2 (Pin 24, Pin 17): Bootstrapped Supplies to the Topside Floating Drivers. ...
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LTC3890-1 FUNCTIONAL DIAGRAM PGOOD1 + 0.88V – V FB1 + – 0.72V 20μA FREQ VCO C LP SYNC DET PLLIN/MODE 100k V IN EXTV CC 5.1V 5.1V LDO LDO – 4.7V SGND INTV CC 10 DUPLICATE FOR ...
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OPERATION (Refer to the Functional Diagram) Main Control Loop The LTC3890-1 uses a constant frequency, current mode step-down architecture with the two controller channels operating 180 degrees out-of-phase. During normal op- eration, each external top MOSFET is turned on when ...
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LTC3890-1 OPERATION (Refer to the Functional Diagram) Light Load Current Operation (Burst Mode Operation, Pulse-Skipping, or Forced Continuous Mode) (PLLIN/MODE Pin) The LTC3890-1 can be enabled to enter high efficiency Burst Mode operation, constant frequency pulse-skipping mode, or forced continuous ...
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OPERATION (Refer to the Functional Diagram) If the PLLIN/MODE pin is not being driven by an external clock source, the FREQ pin can be tied to SGND, tied to INTV or programmed through an external resistor. Tying CC FREQ to ...
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LTC3890-1 OPERATION (Refer to the Functional Diagram) together. The result is a significant reduction in total RMS input current, which in turn allows less expensive input capacitors to be used, reduces shielding requirements for EMI and improves real world operating ...
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APPLICATIONS INFORMATION The Typical Application on the first page is a basic LTC3890-1 application circuit. LTC3890-1 can be configured to use either DCR (inductor resistance) sensing or low value resistor sensing. The choice between the two current sensing schemes is ...
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LTC3890-1 APPLICATIONS INFORMATION Low Value Resistor Current Sensing A typical sensing circuit using a discrete resistor is shown in Figure 4a chosen based on the required SENSE output current. The current comparator has a maximum threshold V . ...
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APPLICATIONS INFORMATION The maximum power loss related to duty cycle, and will occur in continuous mode at the maximum input voltage – V • V IN(MAX) OUT P R1= LOSS R1 Ensure that R1 ...
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LTC3890-1 APPLICATIONS INFORMATION usually provided on the MOSFET manufacturers’ data sheet equal to the increase in gate charge MILLER along the horizontal axis while the curve is approximately flat divided by the specified change in V then multiplied ...
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APPLICATIONS INFORMATION offer much relief. Note that capacitor manufacturers’ ripple current ratings are often based on only 2000 hours of life. This makes it advisable to further derate the capacitor choose a capacitor rated at a higher temperature ...
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LTC3890-1 APPLICATIONS INFORMATION 1/2 LTC3890-1 TRACK/ SGND 38901 F06 Figure 6. Using the TRACK/SS Pin to Program Soft-Start Alternatively, the TRACK/SS pin can be used to track two (or more) supplies during start-up, as shown qualitatively in Figures ...
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APPLICATIONS INFORMATION pin is less than 4.7V, the V LDO is enabled. Power dis- IN sipation for the IC in this case is highest and is equal to V • The gate charge current is dependent on IN ...
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LTC3890-1 APPLICATIONS INFORMATION Topside MOSFET Driver Supply (C External bootstrap capacitors connected to the BOOST B pins supply the gate drive voltages for the topside MOSFETs. Capacitor C in the Functional Diagram is charged though B external diode ...
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APPLICATIONS INFORMATION A shorted top MOSFET will result in a high current condition which will open the system fuse. The switching regulator will regulate properly with a leaky top MOSFET by altering the duty cycle to accommodate the leakage. Phase-Locked ...
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LTC3890-1 APPLICATIONS INFORMATION The minimum on-time for the LTC3890-1 is approximately 90ns. However, as the peak sense voltage decreases the minimum on-time gradually increases up to about TBDns. This is of particular concern in forced continuous applica- tions with low ...
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APPLICATIONS INFORMATION input capacitance requirement over competing solu- tions. Other losses including Schottky conduction losses during dead-time and inductor core losses generally account for less than 2% total additional loss. Checking Transient Response The regulator loop response can be checked ...
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LTC3890-1 APPLICATIONS INFORMATION A 4.7μH inductor will produce 29% ripple current. The peak inductor current will be the maximum DC value plus one half the ripple current, or 5.73A. Increasing the ripple current will also help ensure that the minimum ...
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APPLICATIONS INFORMATION – Are the SENSE and SENSE leads routed together with minimum PC trace spacing? The filter capacitor between + – SENSE and SENSE should be as close as possible to the IC. Ensure accurate current sensing ...
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LTC3890-1 APPLICATIONS INFORMATION ITH1 V R1* SENSE1 C1* SENSE1 FREQ f PLLIN/MODE IN RUN1 RUN2 SGND SENSE2 C2* SENSE2 R2* V ITH2 TRACK/SS2 *R1, R2, C1, C2, D1, D2 ARE OPTIONAL. Figure 11. Recommended Printed Circuit Layout Diagram 28 TRACK/SS1 ...
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APPLICATIONS INFORMATION BOLD LINES INDICATE HIGH SWITCHING CURRENT. KEEP LINES TO A MINIMUM LENGTH. SW1 L1 R SENSE1 D1 C OUT1 SW2 L2 R SENSE2 D2 C OUT2 Figure 12. Branch Current Waveforms LTC3890-1 ...
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LTC3890-1 TYPICAL APPLICATIONS R B1 100k R A1 31.6k C 100pF ITH1A R C 1000pF ITH1 ITH1 34.8k C 0.01μF SS1 R FREQ 41.2k C 0.01μF SS2 R C 470pF ITH2 ITH2 34. 10. 100k MTOP1, ...
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TYPICAL APPLICATIONS R B1 100k R A1 10.5k C 100pF ITH1A R 34.8k ITH1 C ITH1 C 0.01μF SS1 470pF INTV R CC MODE 100k R RUN V OUT 1000k 41.2k FREQ C ITH2 100pF MTOP1, MTOP2, ...
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LTC3890-1 TYPICAL APPLICATIONS R B1 100k R A1 6.98k C 100pF ITH1A R C 470pF ITH1 ITH1 34.8k C 0.01μF SS1 R FREQ 41.2k C 0.01μF SS2 R C 470pF ITH2 ITH2 20k R A2 18. 100k 32 ...
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TYPICAL APPLICATIONS R B1 487k C 33pF 16.9k C 100pF ITH1A R C 680pF ITH1 ITH1 46k C 0.01μF SS1 R FREQ 60k C 0.01μF SS2 R C 470pF ITH2 ITH2 20k 100k 18.7k ...
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LTC3890-1 PACKAGE DESCRIPTION .254 MIN .0165 .0015 RECOMMENDED SOLDER PAD LAYOUT .0075 – .0098 (0.19 – 0.25) .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING NOT TO SCALE * ...
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... Added MP-grade and H-grade. Changes reflected throughout the data sheet. 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. ...
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... TSSOP-20E, 3mm × 4mm QFN-20 ≤ 38V, IN ≤ 24V 50μA/170μA Q ≤ 36V, IN ≤ 10V 30μA/80μA Q ≤ 100V, IN ≤ 0.93V , SSOP-28 IN ≤ 38V 24V 60V OUT(BUCK) OUT(BOOST) LT 0111 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 38901fa ...