LTC1707 LINER [Linear Technology], LTC1707 Datasheet
LTC1707
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LTC1707 Summary of contents
Page 1
... Schottky diode, saving components and board space. Low output voltages down to 0.8V are easily achieved due to the 0.8V internal reference. The LTC1707 comes in an 8-lead SO package. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation. ...
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... RUN/ REF 0V I 100 A REF Note 3: The LTC1707 is tested in a feedback loop that servos V balance point for the error amplifier (V and power Note 4: Dynamic supply current is higher due to the gate charge being A delivered at the switching frequency ORDER PART ...
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... INPUT VOLTAGE (V) Oscillator Frequency vs Temperature 390 380 370 360 350 340 330 320 310 300 125 – 50 – TEMPERATURE ( C) LTC1707 Efficiency vs Load Current 100 2.5V = 3.6V 75 OUT 2.5V Burst Mode OPERATION 70 1000 1 10 OUTPUT CURRENT (mA) ...
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... LTC1707 W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Output Current vs Input Voltage 1000 V = 1.8V OUT 800 V = 1.5V OUT 600 OUT 400 V = 3.3V OUT V = 2.5V OUT V = 2.9V 200 OUT 2.5 3.5 4.5 5.5 8.5 6.5 7.5 INPUT VOLTAGE (V) 1707 G10 Switch Resistance vs Input Voltage 0.9 0.8 0.7 SYNCHRONOUS SWITCH 0.6 0.5 MAIN SWITCH 0.4 0.3 0.2 0.1 0 2.5 3.5 4.5 5.5 6.5 7.5 8.5 INPUT VOLTAGE (V) ...
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... W V SLOPE COMP – EN – + SLEEP + + 0.12V EA – BURST SWITCHING RUN/SOFT R Q START + OVDET – LTC1707 . Grounding Pin 7 forces pulse skipping mode 0.4V 6 – COMP LOGIC AND ANTI- BLANKING SHOOT-THRU CIRCUIT + I RCMP – GND ...
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... Burst Mode Operation The LTC1707 is capable of Burst Mode operation in which the internal power MOSFETs operate intermittently based on load demand. To enable Burst Mode operation, simply allow the SYNC/MODE pin to float or connect logic high ...
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... A 100mV hysteresis ensures reliable operation with noisy input supplies. Low Supply Operation The LTC1707 is designed to operate down to a 2.85V input voltage. At this voltage the converter is most likely to be running at high duty cycles or in dropout where the main ...
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... The actual reduction in average current is less than for peak current. The basic LTC1707 application circuit is shown in Figure 1a. External component selection is driven by the load re- quirement and begins with the selection of L followed by C ...
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... If RUN/SS has been pulled all the way to ground, there will be a delay before the current starts increasing and is given by: t DELAY Pulling the RUN/SS pin below 0.4V puts the LTC1707 into a low quiescent current shutdown (I be driven directly from logic as shown in Figure 5. Diode 8. ...
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... L1, L2, etc. are the individual losses as a percentage of input power. Although all dissipative elements in the circuit produce losses, two main sources usually account for most of the losses in LTC1707 circuits: V quiescent current and I IN losses. The V quiescent current loss dominates the ...
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... PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1707. These items are also illustrated graphically in the layout diagram of Figure 7. Check the following in your layout: R OPTIONAL ...
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... LTC1707 APPLICATIO S I FOR ATIO Design Example As a design example, assume the LTC1707 is used in a single lithium-ion battery-powered cellular phone applica- tion. The V will be operating from a maximum of 4.2V IN down to about 2.85V. The load current requirement is a maximum of 0.3A but most of the time it will be in standby mode, requiring only 2mA ...
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... I V AVX TPSD107M010R0100 TH REF *** AVX TPSC226M016R0375 2 7 RUN/SS SYNC/MODE LTC1707 GND SW R2 422k + C OUT ** 1% 100 F R1 10V 80.6k 1% LTC1707 OUT 3.3V C *** 0. OUT ** CERAMIC 100 F 6.3V 1707 TA01 V 8. OUT *** 0. 16V 1707 TA02 13 ...
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... GND SW R2 169k 80.6k 1% Double Lithium-Ion to 2.5V/0.5A Regulator * SUMIDA CD54-250 AVX TPSC107M006R0150 TH REF *** AVX TPSC226M016R0375 2 7 RUN/SS SYNC/MODE LTC1707 GND SW R2 169k + C 1% 100 F R1 6.3V 80. 3. OUT 2.5V 0.4A † ...
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... TYP 0.014 – 0.019 (0.355 – 0.483) TYP LTC1707 0.150 – 0.157** (3.810 – 3.988 0.004 – 0.010 (0.101 – 0.254) 0.050 (1 ...
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... Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com Single Lithium-Ion to 1.8V/0.3A Regulator * SUMIDA CD54-150 AVX TPSC107M006R0150 TH REF *** TAIYO YUDEN LMK325BJ106K RUN/SS SYNC/MODE LTC1707 GND SW R2 100k + C 1% 100 ...