LTM4608 LINER [Linear Technology], LTM4608 Datasheet
LTM4608
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LTM4608 Summary of contents
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... Fault protection features include overvoltage protection, overcurrent protection and thermal shutdown. The power module is offered in a compact and thermally enhanced 15mm × 9mm × 2.8mm LGA package. The LTM4608 is Pb-free and RoHS compliant . , LT , LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation. μ ...
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... LTM4608EV#PBF LTM4608V LTM4608IV#PBF LTM4608V 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: This product is only offered in trays. For more information go to: ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi ...
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... Load 50 Full Load 1.5V 100μF OUT OUT C = 100μF OUT V = 2.375V 1.5V IN OUT V = 3.3V 1.5V IN OUT 1.5V IN OUT 1.5V 2.375V to 5.5V OUT OUT IN RUN Rising RUN Falling LTM4608 MIN TYP MAX 400 IN 1.15 55 450 IN 1 3.75 4.5 2. ● 0.1 0.2 OUT ● 0.3 0.75 ● 0.3 0. ...
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... MGN = 0V, BSEL = V IN MGN = 0V, BSEL = Float Note 2: The LTM4608E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the – 40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. The LTM4608I is guaranteed and tested over the – ...
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... V (V) IN Load Transient Response 1A/DIV 20mV/DIV 20μs/DIV 3.3V OUT 2A/μs STEP C = 100μF X5R OUT C1 = 100pF , C3 = 22pF FROM FIGURE 18 5.5 LTM4608 per Figure 18 Typcial Application Effi ciency vs Load Current 100 CONTINUOUS MODE 2.5V 1. OUT 2.5V 1.5V IN OUT 2.5V 1.8V IN OUT ...
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... LTM4608 TYPICAL PERFORMANCE CHARACTERISTICS Load Transient Response 2A/DIV 20mV/DIV 4608 G10 20μs/DIV 1.8V OUT 2.5A/μs STEP C = 100μF X5R OUT C1 = NONE NONE FROM FIGURE 18 Start-Up V OUT 0.5V/DIV V IN 2V/DIV 4608 G13 50μs/DIV 1.5V OUT C = 100μF NO LOAD AND 8A LOAD OUT (DEFAULT 100μ ...
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... Negative Input to the Internal I THM Amplifi er. Tie this pin to SGND for single phase operation. For PolyPhase operation, tie the master’s I while connecting all of the I PolyPhase is a registered trademark of Linear Technology Corporation. LTM4608 /2 for 4-phase IN to disable OUT , then the TRACK pin’s IN with a 10k precision resistor ...
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... LTM4608 PIN FUNCTIONS PGOOD (C7): Output Voltage Power Good Indicator. Open-drain logic output that is pulled to ground when the output voltage is not within ±10% of the regulation point. Disabled during margining. RUN (F1): Run Control Pin. A voltage above 1.5V will turn on the module (C3-C5): Switching Node of the Circuit is Used for Testing Purposes ...
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... V IN OUT OPERATION The LTM4608 is a standalone nonisolated switch mode DC/DC power supply. It can deliver output current with few external input and output capacitors. This module provides precisely regulated output voltage programmable via one external resistor from 0. 5.0V DC over a 2.375V to 5.5V input voltage. The typical application schematic is shown in Figure 18 ...
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... phases can be cascaded to run simultaneously with respect to each other by programming the PHMODE pin to different levels. The LTM4608 has clock in and clock out for poly phasing multiple devices or frequency synchronization. High effi ciency at light loads can be accomplished with selectable Burst Mode operation using the MODE pin ...
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... In applications where low output ripple and high effi ciency at intermediate currents are desired, pulse-skipping mode should be used. Pulse-skipping operation allows the LTM4608 to skip cycles at low output loads, thus increasing effi ciency by reducing switching loss. Floating the MODE pin or tying This allows discontinuous conduction mode (DCM) opera- tion down to near the limit defi ...
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... Multiphase Operation TH For output loads that demand more than 8A of current, multiple LTM4608s can be cascaded to run out of phase to provide more output current without increasing input and output voltage ripples. The CLKIN pin allows the LTC4608 to synchronize to an external clock (between 0.75MHz and 2.25MHz) and the internal phase locked ...
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... APPLICATIONS INFORMATION loop allows the LTM4608 to lock onto CLKIN’s phase as well. The CLKOUT signal can be connected to the CLKIN pin of the following LTM4608 stage to line up both the frequency and the phase of the entire system. Tying the PHMODE pin SGND or SV ...
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... Figure 4. Normalized Input RMS Ripple Current vs Duty Factor for One to Six Modules (Phases) 14 frequency of operation (fundamental) and multiples of the operating frequency (harmonics). To reduce this noise, the LTM4608 can run in spread spectrum operation by tying the CLKIN pin spread spectrum operation, the LTM4608’s internal oscillator is designed to produce a clock pulse whose period is random on a cycle-by-cycle basis but fi ...
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... APPLICATIONS INFORMATION same as the slave regulator’s feedback divider to implement coincident tracking. The LTM4608 uses an accurate 10k resistor internally for the top feedback resistor. Figure 5 shows an example of coincident tracking: 10k Slave = 1+ • V TRACK R FB4 V is the track ramp applied to the slave’s track pin. ...
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... LTM4608 APPLICATIONS INFORMATION Ratiometric tracking can be achieved by a few simple calculations and the slew rate value applied to the master’s track pin. As mentioned above, the TRACK pin has a control range from 0V to 0.596V. The master’s TRACK pin slew rate is directly equal to the master’s output slew rate in ...
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... F09 to 1.5V Figure 10. BGA Heat Sink with 3.3V IN OUT 110 120 4608 F11 to 1.5V Figure 12. BGA Heat Sink with 5V IN OUT 110 120 4608 F13 to 2.5V Figure 14. BGA Heat Sink with 3.3V IN OUT LTM4608 400LFM 1 200LFM 0LFM ...
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... LTM4608 APPLICATIONS INFORMATION 400LFM 1 200LFM 0LFM 100 AMBIENT TEMPERATURE (°C) Figure 15. No Heat Sink with 5V Table 4. 1.5V Output DERATING CURVE V (V) IN Figures 9, 11 3.3, 5 Figures 9, 11 3.3, 5 Figures 9, 11 3.3, 5 Figures 10, 12 3.3, 5 Figures 10, 12 3.3, 5 Figures 10, 12 3.3, 5 Table 5. 3.3V Output ...
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... Layout Checklist/Example The high integration of LTM4608 makes the PCB board layout very simple and easy. However, to optimize its electrical and thermal performance, some layout con- siderations are still necessary. • ...
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... LTM4608 APPLICATIONS INFORMATION 5. 10μF MODE PHMODE 5.5V TRACK C2 10μF Figure 19. Two LTM4608s in Parallel, 1.5V at 16A Design 20 CLKIN CLKIN OUT 220pF SW FB LTM4608 R FB RUN I TH 3.09k PLLLPF I THM TRACK PGOOD (HIGH = 10%) BSEL MODE BSEL (FLOAT = 15%) ...
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... APPLICATIONS INFORMATION D1 MMSD4148 SHDN D2 MMSD4148 SHDN Figure 20. Dual LTM4608 Output Sequencing Application V IN 2.5V TO 5.5V CLKIN CLKIN OUT LTM4608 RUN I TH PLLLPF I THM TRACK PGOOD MODE BSEL PHMODE MGN CLKOUT GND SGND R1 100k CLKIN OUT ...
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... LTM4608 APPLICATIONS INFORMATION 22 4608f ...
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... However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights bbb 6.350 5.080 3.810 2.540 1.270 0.381 0.000 0.381 1.270 2.540 3.810 5.080 6.350 LTM4608 4608f 23 ...
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... LTM4608 PACKAGE DESCRIPTION PIN NAME PIN NAME A1 GND B1 GND A2 GND B2 – A3 GND B3 CLKIN A4 GND B4 PHMODE C4 A5 GND B5 MODE A6 GND B6 – A7 GND B7 BSEL A8 GND B8 MGN A9 GND B9 GND A10 GND B10 GND A11 GND B11 GND RELATED PARTS PART NUMBER DESCRIPTION LTC2900 Quad Supply Monitor with Adjustable Reset Timer ...