LTC3727EG-1#PBF Linear Technology, LTC3727EG-1#PBF Datasheet

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... LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 5929620, 6177787, 6144194, 6100678, 5408150, 6580258, 6304066, 5705919 ...

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... Operating Temperature Range (Note 2) .. – 40°C to 85°C Junction Temperature (Note 3) ............................. 125°C Storage Temperature Range ................. – 65°C to 125°C Lead Temperature (Soldering, 10 sec, G Package)............................. 300°C Solder Reflow Temperature (UH Package) ........... 265°C to – 0. ORDER PART NUMBER LTC3727EG LTC3727EG OSENSE1 LTC3727IG-1 PLLFLTR 2 PLLIN 3 FCB TH1 ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Output Voltage Load Regulation LOADREG g Transconductance Amplifier g m1 Transconductance Amplifier GBW mGBW1 Input DC Supply Current Q Normal Mode Shutdown V Forced ...

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... OSENSE V Ramping Negative OSENSE V Ramping Positive OSENSE LTC3727EG/LTC3727EG-1/LTC3727IG-1: T LTC3727EUH-1: T Note 4: The LTC3727/LTC3727-1 are tested in a feedback loop that servos specified voltage and measures the resultant V ITH1, 2 Note 5: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. See Applications Information. ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Input Voltage and Mode (Figure 13) 1000 800 BOTH CONTROLLERS ON 600 400 200 SHUTDOWN INPUT VOLTAGE (V) 3727 G04 Maximum Current Sense Threshold vs ...

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LTC3727/LTC3727 TYPICAL PERFOR A CE CHARACTERISTICS SENSE Pins Total Source Current 100 50 0 –50 –100 –150 –200 –250 –300 –350 –400 COMMON MODE VOLTAGE (V) SENSE 3727 G13 Soft-Start Up (Figure 12) I ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Pin Input Current vs Temperature OUT –50 – 100 125 TEMPERATURE (°C) 3727 G22 Undervoltage Lockout vs Temperature ...

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LTC3727/LTC3727 CTIO S PLLFLTR (Pin 5/Pin 2): The phase-locked loop’s lowpass filter is tied to this pin. Alternatively, this pin can be driven with voltage source to vary the frequency of ...

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CTIO AL DIAGRA PLLIN F PHASE DET IN 50k PLLFLTR CLK1 R LP OSCILLATOR CLK2 C LP – 0.86V + V OSENSE1 PGOOD – + 0.74V 0.86V – OSENSE2 – + 0.74V V 1.5V SEC ...

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LTC3727/LTC3727-1 U OPERATIO (Refer to Functional Diagram) The top MOSFET drivers are biased from floating boot- strap capacitor C , which normally is recharged during B each off cycle through an external diode when the top MOSFET turns off. As ...

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U OPERATIO (Refer to Functional Diagram) Power Good (PGOOD) Pin The PGOOD pin is connected to an open drain of an internal MOSFET. The MOSFET turns on and pulls the pin low when either output is not within ±7.5% of ...

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LTC3727/LTC3727-1 U OPERATIO (Refer to Functional Diagram 2.53A IN(MEAS) (a) Figure 3. Input Waveforms Comparing Single-Phase (a) and 2-Phase (b) Operation for Dual Switching Regulators Converting 12V to 5V and 3. Each. The Reduced Input Ripple ...

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U U APPLICATIO S I FOR ATIO Figure 1 on the first page is a basic LTC3727/LTC3727-1 application circuit. External component selection is driven by the load requirement, and begins with the selection of R and the inductor value. Next, ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO The inductor value also has secondary effects. The transi- tion to Burst Mode operation begins when the average inductor current required results in a peak current below 25% of the current limit ...

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U U APPLICATIO S I FOR ATIO short-circuit when the synchronous switch is on close to 100% of the period. The term (1+δ) is generally given for a MOSFET in the form of a normalized R vs Temperature curve, but ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO The benefit of the LTC3727 multiphase can be calculated by using the equation above for the higher power control- ler and then calculating the loss that would have resulted if both controller ...

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U U APPLICATIO S I FOR ATIO INTV Regulator CC An internal P-channel low dropout regulator produces 7.5V at the INTV pin from the V CC powers the drivers and internal circuitry within the LTC3727. The INTV pin regulator can ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO V IN OPTIONAL EXTV CC CONNECTION + 7.5V < V < 8.5V SEC N-CH LTC3727 TG1 T1 EXTV SW CC 1:N R6 FCB BG1 R5 N-CH SGND PGND Figure ...

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U U APPLICATIO S I FOR ATIO Regulating an output voltage of 1.8V, the maximum value of R1 should be 32K. Note that for an output voltage above 2.4V, R1 has no maximum value necessary to absorb the sense currents; ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO Why should you defeat overcurrent latchoff? During the prototyping stage of a design, there may be a problem with noise pickup or poor layout causing the protection circuit to latch off. Defeating ...

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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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LTC3727/LTC3727 APPLICATIO S I FOR ATIO be drawn from the inductor primary in order to extract power from the auxiliary windings. With the loop in continuous mode, the auxiliary outputs may nominally be loaded without regard to the ...

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U U APPLICATIO S I FOR ATIO which excludes MOSFET driver and control currents; the second is the current drawn from the 3.3V linear regulator output. V current typically results in a small (<0.1%) loss INTV current is ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO overshoot seen at this pin. The bandwidth can also be estimated by examining the rise time at the pin. The I external components shown in the Figure 1 circuit will provide an ...

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U U APPLICATIO S I FOR ATIO Design Example As a design example for one channel, assume V 24V(nominal 30V(max OUT f = 250kHz. The inductance value is chosen first based on a 40% ripple current ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO 2. Are the signal and power grounds kept separate? The combined LTC3727 signal ground pin and the ground return of C must return to the combined C INTVCC terminals. The path formed ...

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U U APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH SWITCHING CURRENT. KEEP LINES TO A MINIMUM LENGTH 6. Keep the switching nodes (SW1, SW2), top gate nodes (TG1, TG2), and boost ...

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LTC3727/LTC3727 APPLICATIO S I FOR ATIO application. The frequency of operation should be main- tained over the input voltage range down to dropout and until the output load drops below the low current opera- tion threshold—typically 10% to ...

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U TYPICAL APPLICATIO S 1 RUN/SS1 0.1μF 2 SENSE1 27pF 1000pF 105k 3 SENSE1 1% 20k OSENSE1 5 0.01μF PLLFLTR 10k 1000pF 6 f PLLIN SYNC 33pF 7 FCB 8 I TH1 15k 220pF 9 SGND 33pF ...

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LTC3727/LTC3727-1 U TYPICAL APPLICATIO S 1 RUN/SS1 0.1μF 2 SENSE1 27pF 1000pF 105k 3 SENSE1 1% 20k OSENSE1 5 PLLFLTR 6 PLLIN 33pF 7 FCB 8 I TH1 15k 220pF 9 SGND 33pF 10 3.3V 3.3V 11 ...

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... PIN 1 TOP MARK (NOTE 6) 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 Package 28-Lead Plastic SSOP (5.3mm) (Reference LTC DWG # 05-08-1640) 1.25 ± ...

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... Dual Synchronous Step-Down Controller ® LTC3729 20A to 200A PolyPhase LTC3731 3-Phase, 600kHz Synchronous Step-Down Controller PolyPhase is a registered trademark of Linear Technology Corporation Pentium is a registered trademark of Intel Corporation. Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...