ltc3729euh-trpbf Linear Technology Corporation, ltc3729euh-trpbf Datasheet
ltc3729euh-trpbf
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ltc3729euh-trpbf Summary of contents
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... Available in 5mm 5mm QFN and 28-Lead SSOP Packages U APPLICATIO S Desktop Computers/Servers Large Memory Arrays DC Power Distribution Systems , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP is a registered trademark of Linear Technology Corporation. PolyPhase is a trademark of Linear Technology Corporation. U TYPICAL APPLICATIO 0.1 F LTC3729 ...
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... RUN/SS CONDITIONS (Note 3); I Voltage = 1.2V TH – SENSE SENSE1, 2 (Note 3) (Note 3) Measured in Servo Loop; I Voltage = 0.7V TH Measured in Servo Loop; I Voltage = 2V TH ORDER PART TOP VIEW NUMBER LTC3729EUH 24 BOOST1 BG1 EXTV INTV CC 19 PGND UH PART 18 BG2 MARKING 17 BOOST2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Reference Voltage Line Regulation REFLNREG V Output Overvoltage Threshold OVL UVLO Undervoltage Lockout g Transconductance Amplifier Transconductance Amplifier Gain mOL I Input DC Supply ...
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... T J dissipation P according to the following formulas: D LTC3729EG • LTC3729EUH • Note 3: The LTC3729 is tested in a feedback loop that servos V specified voltage and measures the resultant TYPICAL PERFOR A CE CHARACTERISTICS ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Input Voltage and Mode 1000 800 600 ON 400 200 SHUTDOWN INPUT VOLTAGE (V) 3729 G04 Internal 5V LDO Line Reg ...
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LTC3729 W U TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 0.0 FCB = 15V IN FIGURE 1 –0.1 –0.2 –0.3 –0 LOAD CURRENT (A) 3729 G13 Maximum Current Sense Threshold vs Temperature ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Pin Input Current vs Temperature OUT –50 – 100 125 TEMPERATURE ( C) 3729 G23 Undervoltage Lockout vs ...
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LTC3729 CTIO S G Package/UH Package PLLFLTR (Pin 5/Pin 2): The Phase-Locked Loop’s Low Pass Filter is tied to this pin. Alternatively, this pin can be driven with voltage source to ...
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CTIO AL DIAGRA PLLIN PHASE DET F IN 50k PLLLPF R LP CLKOUT CLK1 C LP OSCILLATOR CLK2 PHASMD PHASE LOGIC 2 A DIFFOUT 40k 40k – – 40k 40k ...
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LTC3729 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3729 uses a constant frequency, current mode step-down architecture. During normal operation, the top MOSFET is turned on each cycle when the oscillator sets the RS latch, and turned ...
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U OPERATIO (Refer to Functional Diagram) INTV /EXTV Power CC CC Power for the top and bottom MOSFET drivers and most of the IC circuitry is derived from INTV EXTV pin is left open, an internal 5V low dropout CC ...
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LTC3729 U U APPLICATIO S I FOR ATIO When using the controller in very low dropout conditions, the maximum output current level will be reduced due to internal slope compensation required to meet stability criterion for buck regulators operating at ...
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U U APPLICATIO S I FOR ATIO 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0.1 0.2 0.3 0.4 0.5 DUTY FACTOR (V OUT Figure 3. Normalized Peak Output Current vs Duty Factor [I 0 ...
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LTC3729 U U APPLICATIO S I FOR ATIO OUT MAX MAIN MAX RSS – OUT MAX P 1 ...
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U U APPLICATIO S I FOR ATIO This makes it advisable to further derate the capacitor choose a capacitor rated at a higher temperature than required. Several capacitors may also be paralleled to meet size or height requirements ...
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LTC3729 U U APPLICATIO S I FOR ATIO maximum junction temperature rating for the LTC3729 to be exceeded. The supply current is dominated by the gate charge supply current, in addition to the current drawn from the differential amplifier output. ...
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U U APPLICATIO S I FOR ATIO OPTIONAL EXTV CONNECTION < V < SEC LTC3729 V IN 1N4148 TG1 6.8V EXTV CC N-CH SW1 T1 BG1 N-CH PGND Figure 5a. Secondary Output ...
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LTC3729 U U APPLICATIO S I FOR ATIO The time for the output current to ramp up is then RAMP pulling the RUN/SS ...
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U U APPLICATIO S I FOR ATIO The phase detector used is an edge sensitive digital type which provides zero degrees phase shift between the external and internal oscillators. This type of phase detec- tor will not lock up on ...
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LTC3729 U U APPLICATIO S I FOR ATIO Voltage Positioning Voltage positioning can be used to minimize peak-to-peak output voltage excursions under worst-case transient loading conditions. The open-loop DC gain of the control loop is reduced depending upon the maximum ...
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U U APPLICATIO S I FOR ATIO increasingly lower output voltages and higher currents required by high performance digital systems is not dou- bling but quadrupling the importance of loss terms in the switching regulator system! 4) Transition losses apply ...
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LTC3729 U U APPLICATIO S I FOR ATIO Design Example (Using Two Phases design example, assume (nominal (max 1.8V 20A and f = 300kHz. OUT ...
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U U APPLICATIO S I FOR ATIO which is much less than normal, full-load conditions. Incidentally, since the load no longer dissipates power in the shorted condition, total system power dissipation is decreased by over 99%. The duty cycles when ...
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LTC3729 U U APPLICATIO S I FOR ATIO The diagram in Figure 9 illustrates all branch currents in a 2-phase switching regulator. It becomes very clear after studying the current waveforms why it is critical to keep the high-switching-current paths ...
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U U APPLICATIO S I FOR ATIO Simplified Visual Explanation of How a 2-Phase Controller Reduces Both Input and Output RMS Ripple Current A multiphase power supply significantly reduces the amount of ripple current in both the input and output ...
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LTC3729 U TYPICAL APPLICATIO S OPTIONAL SYNC CLOCK IN 1 1000pF 2 0. 8.06k 0. 6800pF 8 47k 100pF 9 25.5k 470pF 13 14 1000pF 24k 75k 1 ...
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... MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U ...
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... Current Mode Synchronous Step-Down Controller SENSE LTC1929/LTC1929-PG 2-Phase Synchronous Controllers LTC3728 550kHz, 2-Phase Dual Output Synchronous Step-Down Controller Burst Mode is a registered trademark of Linear Technology Corporation. Adaptive Power is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www ...