LTC3412A Linear Technology, LTC3412A Datasheet
LTC3412A
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LTC3412A Summary of contents
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... OPTI-LOOP transient response to be optimized over a wide range of loads and output capacitors. The LTC3412A can be confi gured for either Burst Mode operation or forced continuous operation. Forced continu- ous operation reduces noise and RF interference while Burst Mode operation provides high effi ciency by reducing gate charge losses at light loads ...
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... LTC3412AIUF#TRPBF LEAD BASED FINISH TAPE AND REEL LTC3412AEFE LTC3412AEFE#TR LTC3412AIFE LTC3412AIFE#TR LTC3412AEUF LTC3412AEUF#TR LTC3412AIUF LTC3412AIUF#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 ...
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... 5.5V RUN IN Note 3: The LTC3412A is tested in a feedback loop that adjusts V achieve a specifi ed error amplifi er output voltage (I Note 4: Dynamic supply current is higher due to the internal gate charge being delivered at the switching frequency. Note calculated from the ambient temperature T ...
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... LTC3412A W U TYPICAL PERFOR A CE CHARACTERISTICS Effi ciency vs Load Current 100 90 Burst Mode OPERATION 80 70 FORCED 60 CONTINUOUS 3. 2.5V 10 OUT FIGURE 4 CIRCUIT 0 0.01 0.1 1 LOAD CURRENT (A) 3412A GO1 Effi ciency vs Input Voltage 94 FIGURE 4 CIRCUIT 0. 2.5 3.0 3.5 4.0 4.5 INPUT VOLTAGE (V) ...
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... TEMPERATURE (°C) Frequency vs Input Voltage 1060 R = 294k OSC 1050 1040 1030 1020 1010 1000 990 2.5 3.0 3.5 4.0 4.5 940 INPUT VOLTAGE (V) LTC3412A www.DataSheet4U.com V vs Temperature REF 0.7975 V = 3.3V IN 0.7970 0.7965 0.7960 0.7955 0.7950 0.7945 0.7940 0.7935 0.7930 –25 – –45 TEMPERATURE (°C) ...
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... LTC3412A W U TYPICAL PERFOR A CE CHARACTERISTICS Quiescent Current vs Input Voltage 350 300 ACTIVE 250 200 150 100 SLEEP 50 0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) 3412A G19 6 Quiescent Current vs Temperature 350 V = 3.3V IN 300 ACTIVE 250 200 150 100 SLEEP 50 0 –40 – 100 120 TEMPERATURE (° ...
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... RUN/SS (Pin 7/Pin 1): Run Control and Soft-Start Input. Forcing this pin below 0.5V shuts down the LTC3412A. In shutdown all functions are disabled drawing < 1μA of supply current. A capacitor to ground from this pin sets the ramp time to full output current. ...
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... U OPERATIO Main Control Loop The LTC3412A is a monolithic, constant-frequency, current- mode step-down DC/DC converter. During normal opera- tion, the internal top power switch (P-channel MOSFET) is turned on at the beginning of each clock cycle. Current in the inductor increases until the current comparator trips and turns off the top power MOSFET ...
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... R pin is TH P-channel and N-channel power switches increases. The user should calculate the power dissipation when the LTC3412A is used at 100% duty cycle with low input volt- ages to ensure that thermal limits are not exceeded. LTC3412A www.DataSheet4U.com voltage drops below 400mV. At ...
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... MOSFET will be held off and switching cycles will be skipped until the inductor current is reduced. The basic LTC3412A application circuit is shown in Fig- ure 1. External component selection is determined by the maximum load current and begins with the selection of ...
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... V When choosing the input and output ceramic capacitors, choose the X5R or X7R dielectric formulations. These dielectrics have the best temperature and voltage charac- teristics of all the ceramics for a given value and size. LTC3412A www.DataSheet4U.com , is determined by: OUT 1 ESR + ...
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... The RUN/SS pin provides a means to shut down the is set at 6A. For BURST LTC3412A as well as a timer for soft-start. Pulling the is set at 0A. As RUN/SS pin below 0.5V places the LTC3412A in a low quiescent current shutdown state (I The LTC3412A contains an internal soft-start clamp that gradually raises the clamp on I regardless of pulled above 2V ...
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... If the junction temperature reaches approximately 150°C, both power switches will be turned off and the SW node will become high impedance. To avoid the LTC3412A from exceeding the maximum junc- tion temperature, the user will need to do some thermal analysis. The goal of the thermal analysis is to determine whether the power dissipated exceeds the maximum junction temperature of the part ...
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... The I pin external components and output capacitor shown in Figure 1 will provide adequate compensation for most applications. Design Example As a design example, consider using the LTC3412A in an application with the following specifi cations 3.3V 2.5V ...
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... X7R ITH R3 115k R SS 2.2M * VISHAY IHLP-2525CZ-01 ** TDK 4532X5R0J107M Figure 4. 3.3V to 2.5V, 3A Regulator at 1MHz, Burst Mode Operation Connect the V The resistor divider must be connected between V and SGND. Figure 3. LTC3412A Layout Diagram C 22pF X5R FF R1 392k 100k 2 15 PGOOD ...
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... C SS 1000pF X7R 2 3 SGND 47pF X5R R1 232k 100k 2 15 PGOOD SW R ITH 15k LTC3412A 47pF 13 EFE PGND PGND 69. OSC SW 294k 6 SYNC/MODE 7 10 RUN 1000pF X7R 8 9 SGND ...
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... 162k 12 PGND 182k 11 OSC SW 6 1.8MHz SYNC/MODE EXT CLOCK 7 10 RUN 1000pF X7R 8 9 SGND PV IN LTC3412A www.DataSheet4U.com IN3 100μ IN1 22μF 15 X5R 6.3V 14 L1* 13 0.47μH V OUT 3. OUT 100μF 10 ×2 ...
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... LTC3412A PACKAGE DESCRIPTIO 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 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE Package 16-Lead Plastic TSSOP (4.4mm) (Reference LTC DWG # 05-08-1663) Exposed Pad Variation BA 2 ...
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... UF Package 16-Lead Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1692) 0.72 ±0.05 PACKAGE OUTLINE 0.30 ±0.05 0.65 BSC 0.75 ± 0.05 2.15 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC3412A www.DataSheet4U.com BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP R = 0.115 OR 0.35 × 45° CHAMFER TYP 15 16 0.55 ± 0. (UF16) QFN 10-04 0.30 ± ...
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... LTC3412A RELATED PARTS PART NUMBER DESCRIPTION LTC1878 600mA (I ), 550kHz, Synchronous Step-Down DC/DC Converter OUT LTC1879 1.20A (I ), 550kHz, Synchronous Step-Down DC/DC Converter OUT LT1934/LT1934-1 300mA (I ), Constant Off-Time, High Effi ciency Step-Down OUT DC/DC Converter LTC3404 600mA (I ), 1.4MHz, Synchronous Step-Down DC/DC Converter OUT LTC3405/LTC3405A 300mA (I ), 1.5MHz, Synchronous Step-Down DC/DC Converter ...