LTC1628CG-SYNC#TRPBF Linear Technology, LTC1628CG-SYNC#TRPBF Datasheet

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... LTC and LT 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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... Peak Output Current <10µs (TG1, TG2, BG1, BG2) ... 3A INTV Peak Output Current ................................ 50mA CC Operating Temperature Range LTC1628CG-SYNC ................................... 0°C to 85°C LTC1628IG-SYNC ............................... – 40°C to 85°C Junction Temperature (Note 2) ............................. 125°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER UVLO Undervoltage Lockout V Feedback Overvoltage Lockout OVL I Sense Pins Total Source Current SENSE DF Maximum Duty Factor MAX I Soft-Start Charge Current RUN/SS1 RUN/SS ...

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LTC1628-SYNC ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER PGOOD Output V PGOOD Voltage Low PGL I PGOOD Leakage Current PGOOD V PGOOD Trip Level, Either Controller PG Note 1: Absolute Maximum Ratings are those values beyond ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Internal 5V LDO Line Regulation 5 1mA LOAD 5.0 4.9 4.8 4.7 4.6 4.5 4 INPUT VOLTAGE (V) 1628 G07 Maximum Current Sense ...

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LTC1628-SYNC W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Threshold vs Temperature –50 – 100 125 TEMPERATURE (°C) 1628 G17 Soft-Start Up (Figure 14) V OUT 5V/DIV V ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Pin Input Current vs Temperature OUT –50 – 125 100 TEMPERATURE (°C) 1628 G26 Undervoltage Lockout vs Temperature ...

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LTC1628-SYNC CTIO S RUN/SS1, RUN/SS2 (Pins 1, 15): Combination of soft- start, run control inputs and short-circuit detection timers. A capacitor to ground at each of these pins sets the ramp time to full output ...

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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 SEC 3V ...

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LTC1628-SYNC U OPERATIO (Refer to Functional Diagram) increase until the average inductor current matches the new load current. After the top MOSFET has turned off, the bottom MOSFET is turned on until either the inductor current starts to reverse, as ...

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U OPERATIO (Refer to Functional Diagram) Output Overvoltage Protection An overvoltage comparator, OV, guards against transient overshoots (>7.5%) as well as other more serious condi- tions that may overvoltage the output. In this case, the top MOSFET is turned off ...

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LTC1628-SYNC 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 LTC1628-SYNC 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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LTC1628-SYNC U U 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 synchronous MOSFET losses are greatest at high input voltage when the top switch duty factor is low or during a short-circuit when the synchronous switch is on close to 100% of the period. ...

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LTC1628-SYNC U U APPLICATIO S I FOR ATIO the design. Always consult the manufacturer if there is any question. The benefit of the LTC1628-SYNC multiphase can be calculated by using the equation above for the higher power controller and then ...

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U U APPLICATIO S I FOR ATIO INTV Regulator CC An internal P-channel low dropout regulator produces 5V at the INTV pin from the V supply pin. INTV CC IN the drivers and internal circuitry within the LTC1628- SYNC. The ...

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LTC1628-SYNC U U APPLICATIO S I FOR ATIO output-derived voltage that has been boosted to greater than 4.7V. This can be done with either the inductive boost winding as shown in Figure 6a or the capacitive charge pump shown in ...

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U U APPLICATIO S I FOR ATIO ⎛ ⎞ ⎜ ⎟ ( MAX ) ⎝ ⎠ – OUT for V < 2.4V OUT Regulating an output ...

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LTC1628-SYNC U U 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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LTC1628-SYNC U U APPLICATIO S I FOR ATIO power from the auxiliary windings. With the loop in continuous mode, the auxiliary outputs may nominally be loaded without regard to the primary output load. The secondary output voltage V SEC shown ...

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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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LTC1628-SYNC U U 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 12V(nominal 22V(max OUT and f = 300kHz. The inductance value is chosen first based on a 30% ripple ...

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LTC1628-SYNC U U APPLICATIO S I FOR ATIO PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1628-SYNC. These items are also illustrated graphi- cally in ...

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U U APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH. signal ground. The R2 and R4 connections should not be along the high ...

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LTC1628-SYNC U U APPLICATIO S I FOR ATIO 7. Use a modified “star ground” technique: a low imped- ance, large copper area central grounding point on the same side of the PC board as the input and output capacitors with ...

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U TYPICAL APPLICATIO S 59k 1 RUN/SS1 0.1µ SENSE1 180pF 1000pF 3 – SENSE1 105k OSENSE1 20k 5 1% INTV PLLFLTR CC 6 PLLIN 33pF 7 FCB LTC1628-SYNC 8 I TH1 15k 1000pF 9 SGND ...

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LTC1628-SYNC 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 ...

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... FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE 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. ...

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... PolyPhase Synchronous Controller Expandable from 2-Phase to 12-Phase, Uses All Surface Mount LTC3731 3- to 12-Phase Step-Down Synchronous Controller LTC3827-1 Low I 2-Phase Duel Synchronous Controller Q 10A DC/DC µModule LTM4600 No R and PolyPhase are trademarks of Linear Technology Corporation. SENSE Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ● I ...