LTC3127 Linear Technology, LTC3127 Datasheet
LTC3127
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LTC3127 Summary of contents
Page 1
... Other features include <1μA shutdown current, pin-selectable Burst Mode operation and thermal overload protection. The LTC3127 is housed in thermally enhanced 10-lead (3mm × 3mm × 0.75mm) DFN packages and 12-lead MSOP packages. L, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks and PowerPath and ThinSOT are trademarks of Linear Technology Corporation ...
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... TAPE AND REEL LTC3127EDD#PBF LTC3127EDD#TRPBF LTC3127EMSE#PBF LTC3127EMSE#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: For more information on tape and reel specifications, go to: ...
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... Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3127 is guaranteed to meet performance specifications from 0°C to 85°C. Specifications over the –40°C to 85°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LTC3127 Typical perForMance characTerisTics Efficiency vs Load Current 100 PWM V = 1.8V OUT 90 80 BURST 100 LOAD CURRENT (mA) 3127 G01 Average Input Current Limit vs V (Normalized 3.3V OUT R = 32.4k PROG 1 0 –1 –2 –3 –4 –5 3.4 5.4 1.8 2.2 2.6 3 3.8 4.2 4 ...
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... V (V) IN Burst Mode Operation I L 500mA/DIV V OUT 20mV/DIV 3127 G15 = 3. 4.4mF R PROG R3 = 499k LTC3127 www.DataSheet4U.com (T = 25°C, unless otherwise noted ) J NMOS DS(ON) IN 300 250 200 SWC 150 SWB 100 1.8 2.4 3 3.6 1000 V (V) IN 3127 G10 Load Transient Response in Fixed Frequency Mode, No Load to 1A, ...
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... LTC3127 Typical perForMance characTerisTics Load Transient Response in Burst Mode Operation, No Load to 1A, Not in Input Current Limit I LOAD 1A/DIV I IN 1A/DIV V OUT 50mV/DIV MODE 5V/DIV 200µs/DIV OUT R = 90k C PROG OUT R3 = 499k C1 = 100pF Load Transient Response in Burst Mode Operation, No Load ...
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... Output capacitors must be low ESR. SW2 (Pin 10): Switch Pin Where Internal Switches C and D Are Connected. Minimize trace length to reduce EMI. PGND (Exposed Pad Pin 11): Power Ground. The exposed pad must be soldered to the PCB ground plane. LTC3127 www.DataSheet4U.com • ...
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... LTC3127 block DiagraM – PEAK AMP SHDN MODE SAMPLE/HOLD AND RESET PROG V CLAMP R PROG L SW1 SW2 I ZERO AMP PWM COMPARATOR + AND LOGIC – www.DataSheet4U.com V OUT OUT FB – 1.195V + R1 – + SGND 3127 BD R3 3127f ...
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... The LTC3127 is an average input current controlled buck- boost DC/DC converter offered in both a thermally enhanced 3mm × 3mm DFN package and a thermally enhanced 12- lead MSOP package. The buck-boost converter utilizes a proprietary switching algorithm which allows its output voltage to be regulated above, below or equal to the input voltage ...
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... When compensating the converter with integral compen- sation it is important to consider that the total bandwidth of the network must be below 15kHz. The inner current loop of the LTC3127 eliminates one of the double poles caused by the inductor. The output capacitor causes a dominant pole and also a zero, and the resistor divider sets the gain ...
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... D will be turned off for the remainder of the switching cycle. Burst Mode Operation When the MODE pin is held high the LTC3127 will func- tion in Burst Mode operation as long as the load current is typically less than 35mA. In Burst Mode operation, the LTC3127 still switches at a fixed frequency of 1 ...
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... LTC3127 applicaTions inForMaTion A typical LTC3127 application circuit is shown on the front page of this data sheet. The external component selection is determined by the desired output voltage, input current and ripple voltage requirements for each particular applica- tion. However, basic guidelines and considerations for the design process are provided in this section ...
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... V DROOP High capacitance values and low ESR can lead to instability in typical internally compensated buck-boost convert- ers. Using proportional compensation, the LTC3127 is stable with low ESR output capacitor values greater than 1000µF . Multilayer ceramic capacitors are an excellent choice for input decoupling of the step-up converter as they have extremely low ESR and are available in small footprints. ...
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... LTC3127 applicaTions inForMaTion Capacitor Selection Example In this example, a pulsed load application requires that V droops less than 300mV. The application is a Li-Ion OUT battery input to a 3.6V output. The pulsed load is a no-load to a 1.5A step with a frequency of 217Hz and a duty cycle of 12.5%. The input current limit is set to 500mA. In order ...
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... The LTC3127 switches large currents at high frequencies. Special care should be given to the PCB layout to ensure stable, noise-free operation. Figure 4 depicts the recom- mended PCB layout to be utilized for the LTC3127. A few key guidelines follow: 1. All circulating high current paths should be kept as short as possible ...
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... USB (500mA Max), 3.8V GSM Pulsed Load L1 4.7µH SW1 SW2 OUT MODE LTC3127 FB SHDN V PROG 10µF C SGND PGND 100pF 32.4k L1 4.7µH SW1 SW2 OUT MODE LTC3127 FB SHDN PROG V 10µF C SGND PGND 100pF 32.4k www.DataSheet4U.com V OUT 3.8V 2.15M C1 C2 2.2mF 2.2mF 1M 499k 3127 TA02 V OUT 3.8V 2.15M C3 2.2mF ...
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... LTC3127 FB SHDN V PROG C 10µF SGND PGND 100pF 60.4k L1 4.7µH SW1 SW2 OUT FB MODE LTC3127 SHDN V PROG C SGND PGND 47k 60.4k 0.01µF LTC3127 www.DataSheet4U.com V OUT 5V 100k 3.16M C1 100F 1M 100k C2 100F 499k 3127 TA04 V OUT 3.3V 33pF 316k 22µF 182k 2 3300pF 3127 TA05 3127f ...
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... LTC3127 package DescripTion 3.55 0.05 1.65 0.05 2.15 0.05 (2 SIDES) 0.25 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE 5 ...
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... DETAIL “A” 1.10 (.043) MAX SEATING PLANE 0.22 – 0.38 (.009 – .015) 0.650 TYP (.0256) BSC LTC3127 www.DataSheet4U.com 6 0.35 REF 0.12 REF DETAIL “B” CORNER TAIL IS PART OF DETAIL “B” THE LEADFRAME FEATURE. FOR REFERENCE ONLY 7 NO MEASUREMENT PURPOSE (NOTE 3) ...
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... Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● L1 4.7µH SW1 SW2 OUT MODE LTC3127 FB SHDN ON PROG 10µF SGND PGND 60.4k 100pF COMMENTS 95% Efficiency < 1µA, 4mm × 4mm QFN-24 Package SD 94% Efficiency, V 2mm × 3mm DFN-8 Package 95% Efficiency, V 3mm × ...