LTC3417A LINER [Linear Technology], LTC3417A Datasheet
LTC3417A
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LTC3417A Summary of contents
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... Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131, 6144194 2.2µH V OUT2 SW2 2.5V 22pF 1A RUN2 V IN 866k V FB2 22µF 412k I TH2 2.87k 6800pF 3417 TA01 LTC3417A Dual Synchronous 1.5A/1A 4MHz U OUT2 Efficiency (Burst Mode Operation) 100 10 REFER TO FIGURE 4 95 EFFICIENCY 1 90 0.1 85 0.01 80 POWER LOSS 0.001 3.6V ...
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... TH1 TH2(PINLOAD 0.75V, V FB1 FB2 SYNC/MODE RUN1 RUN2 IN ORDER PART TOP VIEW NUMBER 20 GNDD 19 PGND1 LTC3417AEFE 18 SW1 LTC3417AIFE 17 PHASE 16 GNDA 21 15 FREQ 14 PGOOD 13 SW2 12 SYNC/MODE 11 PGND2 FE PACKAGE = 125°C, θ = 38° 25°C. A MIN TYP MAX 2 ...
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... The LTC3417AI is guaranteed to meet performance specifications over the –40°C to 85°C operating temperature range. Note 3: The LTC3417A is tested in feedback loop which servos V midpoint for the error amplifier (V = 0.6V) and V ITH1 the error amplifier ( ...
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... LTC3417A W TYPICAL PERFOR A CE CHARACTERISTICS OUT1 Burst Mode Operation V OUT 20mV/DIV I L 250mA/DIV V = 3.6V 2µs/DIV 1.8V OUT I = 100mA LOAD REFER TO FIGURE 4 OUT2 Burst Mode Operation V OUT 20mV/DIV I L 250mA/DIV V = 3.6V 2µs/DIV 2.5V OUT I = 60mA LOAD REFER TO FIGURE 4 OUT1 Efficiency vs Load Current ...
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... FREQUENCY (MHz) Frequency FREQ = 143k TO GROUND 0 –2 –4 FREQ = V IN –6 –8 –10 5.5 2 2.5 3 3.5 4 4.5 V (V) IN LTC3417A Load Step OUT2 V OUT2 100mV/DIV I OUT2 500mA/DIV 3417 G11 V = 3.6V 100µs/DIV 2.5V OUT I = 0.25A to 0.8A LOAD REFER TO FIGURE OUT1 DS(ON) IN ...
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... LTC3417A CTIO S (DFN/TSSOP) RUN1 (Pin 1/Pin 2): Enable for 1.5A Regulator. When at Logic 1, 1.5A regulator is running. When at 0V, 1.5A regulator is off. When both RUN1 and RUN2 are at 0V, the part is in shutdown. V (Pin 2/Pin 3): Supply Pin for P-Channel Switch of IN1 1.5A Regulator. I (Pin 3/Pin 4): Error Amplifier Compensation Point for TH1 1 ...
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... V FB2 – REGULATOR W I TH1 I TH LIMIT – LOGIC V IN2 LOGIC + V B – LIMIT I TH2 LTC3417A V IN1 + – SLOPE COMPENSATION ANTI-SHOOT- SW1 THROUGH + – – PGND1 + PGOOD PHASE OSCILLATOR FREQ PGND2 + – – + SW2 ANTI-SHOOT- THROUGH SLOPE COMPENSATION – ...
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... For lower output voltage ripple at low currents, pulse skipping mode can be used. In this mode, the LTC3417A continues to switch at constant frequency down to very low currents, where it will begin skipping pulses used to control the power MOSFETs ...
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... P- channel MOSFET and inductor APPLICATIO S I FOR ATIO A general LTC3417A application circuit is shown in Figure 4. External component selection is driven by the load requirement, and begins with the selection of the inductors L1 and L2. Once L1 and L2 are chosen and C can be selected ...
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... Sumida CDRH3D16/HP 2R2 CDRH2D18/HP 2R2 Midcom DUP-1813-2R2R LTC3417A requires to operate. Table 1 shows some is the maximum typical surface mount inductors that work well in , occurs at the LTC3417A applications. L Input Capacitor (C In continuous mode, the input current of the converter can be approximated by the sum of two square waves with ...
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... An excellent choice is the AVX TPS series of surface tantalums, available in case heights ranging from 2mm to 4mm. Aluminum electrolytic capacitors have a for IN significantly larger ESR, and are often used in extremely cost-sensitive applications provided that consideration is LTC3417A and C ) Selection OUT1 OUT2 and C is driven by the required ...
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... Panasonic specialty polymer (SP) capacitors. In most cases, 0.1µF to 1µF of ceramic capacitors should also be placed close to the LTC3417A in parallel with the main capacitors for high frequency decoupling. Ceramic Input and Output Capacitors Higher value, lower cost ceramic capacitors are now becoming available in smaller case sizes ...
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... Soft-start reduces surge currents from V increasing the peak inductor current. Power supply se- quencing can also be accomplished by controlling the I pin. The LTC3417A has an internal digital soft-start for each regulator output, which steps up a clamp on I 1024 clock cycles, as can be seen in Figures 2 and 3. As the ...
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... P1, P2, etc. are the individual losses as a percentage of input power. Although all dissipative elements in the circuit produce losses, four main sources account for most of the losses in LTC3417A circuits: 1) LTC3417A I ing losses The I S electrical characteristics which excludes MOSFET driver and control currents ...
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... The junction temperature has adequate example, consider the case when the LTC3417A is at the switching COUT in dropout in both regulators at an input voltage of 3.3V with load currents of 1.5A and 1A. From the Typical Performance Characteristics graph of Switch Resistance, LTC3417A = P • ...
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... The compensation should be optimized for these compo- nents by examining the load step response, but a good L ). Reasonable values place to start for the LTC3417A is with a 5.9kΩ and 2200pF filter on I capacitor may need to be increased depending on the actual undershoot during a load step. ∆I ...
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... OUT1 Efficiency vs Load Current 100 1.8V OUT FREQ = 1MHz 95 REFER TO FIGURE 4 90 EFFICIENCY 85 POWER LOSS 0.001 0.01 0.1 1 LOAD CURRENT (A) Figure 4. 1.8V at 1.5A/2. Step-Down Regulators LTC3417A R7 100k L2 2.2µH V OUT2 2.5V C2 22pF 866k C R4 OUT2 IN 22µF 412k R6 2.87k C4 6800pF 3417 F04 : KEMET C1206C106K4PAC ...
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... APPLICATIO S I FOR ATIO Board Layout Considerations When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC3417A. These items are also illustrated graphically in the layout diagram of Figure 5. Check the following in your layout. 1. Does the capacitor C ...
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... BSC 0.195 – 0.30 (.0077 – .0118) TYP 4. RECOMMENDED MINIMUM PCB METAL SIZE FOR EXPOSED PAD ATTACHMENT MILLIMETERS (INCHES) *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.150mm (.006") PER SIDE LTC3417A R = 0.115 TYP 0.20 TYP 1.65 ± 0.10 3.00 ±0.10 (2 SIDES) (2 SIDES) 8 0.25 ± ...
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... LTC3417A RELATED PARTS PART NUMBER DESCRIPTION LTC3404 600mA (I ), 1.4MHz, Synchronous Step-Down DC/DC OUT Converter LTC3405/LTC3405A 300mA (I ), 1.5MHz, Synchronous Step-Down DC/DC OUT Converters LTC3406/LTC3406B 600mA (I ), 1.5MHz, Synchronous Step-Down DC/DC OUT Converters LTC3407 Dual 600mA (I ), 1.5MHz, Synchronous Step-Down DC/DC 95% Efficiency, V OUT Converter LTC3407-2 Dual 800mA (I ), 2.25MHz, Synchronous Step-Down ...