LTC3417A-1 Linear Technology, LTC3417A-1 Datasheet
LTC3417A-1
Related parts for LTC3417A-1
LTC3417A-1 Summary of contents
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... Patents including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131, 6144194. 100k RESET 2.2μH V OUT2 2.5V 22pF 866k 22μF 412k 2.87k 6800pF 3417A-1 TA01 LTC3417A-1 www.DataSheet4U.com Dual Synchronous OUT2 Effi ciency (Burst Mode Operation) 100 10 REFER TO FIGURE EFFICIENCY 90 0.1 85 0.01 POWER LOSS 80 0.001 ...
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... LTC3417A-1 ABSOLUTE MAXIMUM RATINGS Voltages ...................................... – 0. IN1 IN2 SYNC/MODE, SW1, SW2, RUN1, RUN2 PHASE, FREQ, FB1 FB2 Voltages........ –0.3V to ((V TH1 TH2 V – – V .......................................... 0.3V IN1 IN2 IN2 IN1 PIN CONFIGURATION TOP VIEW RUN1 IN1 ...
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... Ramping Up IN1 IN2 Ramping Up FB1 FB2 Voltage from Ramping Down FB1 FB2 FREQ = V IN FREQ Tied to GND Through 143k Resistor V = 6V, Pin Under Test = 3V IN LTC3417A-1 www.DataSheet4U.com MIN TYP MAX l 0.784 0.8 0.816 0.02 0.02 –0.02 1400 = V , 400 260 IN RUN1 ...
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... The LTC3417AI-1 is guaranteed to meet performance specifi cations over the –40°C to 125°C operating temperature range. Note 3: The LTC3417A-1 is tested in feedback loop which servos V the midpoint for the error amplifi 0.6V) and V ITH1 for the error amplifi ...
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... LOAD REFER TO FIGURE 4 Effi ciency vs Frequency OUT2 27° 3. OUT I OUT FREQUENCY (MHz) LTC3417A-1 www.DataSheet4U.com OUT1 Effi ciency (Burst Mode Operation) 100 V = 1.8V OUT 95 I LOAD 1.4A LOAD REFER TO FIGURE 2.5 3 3.5 4 ...
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... LTC3417A-1 TYPICAL PERFORMANCE CHARACTERISTICS OUT2 DS(ON 27°C A 0.19 P-CHANNEL SWITCH 0.18 0.17 0.16 0.15 N-CHANNEL SWITCH 0. 2.5 3 3.5 4.5 V (V) IN 3417A-1 G16 PIN FUNCTIONS (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 ...
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... SLOPE COMPENSATION + ANTI-SHOOT- THROUGH – + LOGIC – V IN2 OSCILLATOR – LOGIC + – ANTI-SHOOT- THROUGH + SLOPE COMPENSATION + V – B – LIMIT I TH2 LTC3417A-1 www.DataSheet4U.com V IN1 + – SW1 + – – PGND1 + POR DELAY PHASE FREQ PGND2 + – – + SW2 – IN2 3417A-1 BD 3417a1fa 7 ...
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... For lower output voltage ripple at low currents, pulse skip- ping mode can be used. In this mode, the LTC3417A-1 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. APPLICATIONS INFORMATION A general LTC3417A-1 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, C ...
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... The choice of which style inductor to use often depends more on the price vs size requirements of any radiated fi eld/EMI requirements than on what the LTC3417A-1 requires to operate. Table 1 shows some Table 1 MANUFACTURER PART NUMBER L1 on OT1 ...
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... In addition, the high Q of ceramic capacitors along with trace inductance ) Selection can lead to signifi cant ringing. Other capacitor types include the Panasonic specialty polymer (SP) capacitors. LTC3417A-1 www.DataSheet4U.com ESR ...
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... LTC3417A-1 APPLICATIONS INFORMATION In most cases, 0.1μF to 1μF of ceramic capacitors should also be placed close to the LTC3417A-1 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. Because the LTC3417 control loop does not depend on the output capacitor’ ...
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... In many cases, the output voltage can be simply connected to the SYNC/MODE pin, selecting the forced continuous mode except at start-up. The LTC3417A-1 can be synchronized to an external clock signal by the SYNC/MODE pin. The internal oscillator fre- quency should be set to 20% lower than the external clock frequency to ensure adequate slope compensation, since slope compensation is derived from the internal oscillator ...
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... LTC3417A-1 APPLICATIONS INFORMATION The I external components shown in the Figure 4 circuit TH will provide an adequate starting point for most applica- tions. The series RC fi lter sets the dominant pole-zero loop compensation. The values can be modifi ed slightly (from 0 times their suggested values) to optimize transient response once the fi ...
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... The junction temperature RISE As an example, consider the case when the LTC3417A dropout in both regulators at an input voltage of 3.3V with load currents of 1.5A and 1A. From the Typical Per- formance Characteristics graph of Switch Resistance, the R resistance of the 1.5A P-channel switch is 0.09Ω ...
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... The compensation should be optimized for these compo- L nents by examining the load step response, but a good ). Reasonable values place to start for the LTC3417A-1 is with a 5.9kΩ and 2200pF fi lter on I output capacitor may need to be increased depending on the actual undershoot during a load step. ...
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... OUT1 Effi ciency 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) 3417A-1 F04a Figure 4. 1.8V at 1.5A/2. Step-Down Regulators LTC3417A-1 www.DataSheet4U.com R7 100k RESET V OUT2 2. 22pF 1A 2.2μ 866k C R4 OUT2 V IN 22μF 412k R6 2.87k C4 ...
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... APPLICATIONS INFORMATION Board Layout Considerations When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC3417A-1. These items are also illustrated graphically in the layout diagram of Figure 5. Check the following in your layout. 1. Does the capacitor C connect to the power V ...
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... 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-1 www.DataSheet4U.com R = 0.115 TYP 0.20 TYP 3.00 ± 0.10 1.65 ± 0.10 ...
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... LTC3417A-1 RELATED PARTS PART NUMBER DESCRIPTION LTC3406A/B 600mA, 1.5MHz, Synchronous Step-Down DC/DC Converter LTC3407A Dual 600mA/600mA 1.5MHz, Synchronous Step-Down DC/DC Converter LTC3409 600mA, 1.7/2.6MHz, Synchronous Step-Down DC/DC Converter LTC3410/B 300mA, 2.25MHz, Synchronous Step-Down DC/DC Converter LTC3411A 1.25A, 4MHz, Synchronous Step-Down DC/DC Converter LTC3412A 2.5A, 4MHz, Synchronous Step-Down DC/DC Converter ...