LTC3732CG Linear Technology, LTC3732CG Datasheet
LTC3732CG
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LTC3732CG Summary of contents
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... MOSFETs and the load. A foldback current circuit also provides protection for the external MOSFETs under short-circuit or overload conditions. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode, OPTI-LOOP and PolyPhase are registered trademarks of Linear Technology Corporation. Stage Shedding is a trademark of Linear Technology Corporation ...
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... Operating Ambient Temperature Range ....... Junction Temperature (Notes ................... 125 C ) .... 7V to –0.3V Storage Temperature Range ..................– 150 ..................... 5A Lead Temperature (Soldering, 10 sec) N SSOP Package .................................................. 300 C Reflow Peak Body Temperature to –0.3V QFN Package .................................................... 240 ORDER PART NUMBER LTC3732CG – DIFFOUT 3 EAIN 4 PADDLE 5 SGND 6 + SENSE1 7 – ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER g Transconductance Amplifier Transconductance Amplifier GBW mOL V Forced Continuous Threshold FCB I FCB Bias Current FCB V Burst Inhibit Threshold BINHIBIT UVR Undervoltage RUN/SS Reset ...
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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. A maximum current of 200 A is allowed to pull-up the RUN/SS pin to prevent overcurrent shutdown. Note calculated from the ambient temperature T J dissipation P according to the following formula: D LTC3732CG C/ LTC3732CUHF ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs I (Figure 14) OUT 100 V = OPEN 90 FCB FCB FCB ...
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LTC3732 W U TYPICAL PERFOR A CE CHARACTERISTICS Short-Circuit Arming and Latchoff vs Temperature 5 ARMING 4 LATCHOFF –45 –30 – TEMPERATURE ( C) 3732 G10 Maximum I vs ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Error Amplifier Gain-Phase 10k AC LOAD L 5 100 1k 10k FREQUENCY (Hz) Shed Mode at 1Amp, Light Load Current (Circuit of Figure 14) ...
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LTC3732 CTIO S VID0 to VID4: Output Voltage Programming Input Pins internal pull-up current is provided on each input pin. See Table 1 for details. Do not apply voltage to these pins ...
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CTIO AL DIAGRA PLLIN F PHASE DET IN 50k PLLFLTR R LP CLK1 C LP CLK2 OSCILLATOR CLK3 FCB + FCB – 0.6V PGOOD – + 100 s DELAY – PROTECTION + – IN 40k 40k – ...
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LTC3732 U OPERATIO (Refer to Functional Diagram) voltage. When the load current increases, it causes a slight decrease in the EAIN pin voltage relative to the 0.6V reference, which in turn causes the I until each inductor’s average current matches ...
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U OPERATIO (Refer to Functional Diagram) Frequency Synchronization The phase-locked loop allows the internal oscillator to be synchronized to an external source using the PLLIN pin. The output of the phase detector at the PLLFLTR pin is also the DC ...
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LTC3732 U OPERATIO (Refer to Functional Diagram) voltage ripple requirements. Once the inductors and operating frequency have been chosen, the current sens- ing resistors can be calculated. Next, the power MOSFETs and Schottky diodes are selected. Finally ...
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U U APPLICATIO S I FOR ATIO tions having a highly varying input voltage, additional phases will produce the best results. Accepting larger values of I allows the use of low L inductances but can result in higher output voltage ...
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LTC3732 U U APPLICATIO S I FOR ATIO The curve is generated by forcing a constant input current into the gate of a common source, current source loaded stage and then plotting the gate voltage versus time. The initial slope ...
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U U APPLICATIO S I FOR ATIO Schottky is generally a good compromise for both regions of operation due to the relatively small average current. Larger diodes result in additional transi- tion loss due to their ...
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LTC3732 U U APPLICATIO S I FOR ATIO The selection driven by the required effective OUT series resistance (ESR). Typically once the ESR require- ment is satisfied the capacitance is adequate for filtering. The steady-state output ripple ...
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U U APPLICATIO S I FOR ATIO bypassing close to the IC is necessary to supply the high transient currents required by the MOSFET gate drivers while keeping the 5V supply quiet enough so as not to disturb the very ...
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LTC3732 U U APPLICATIO S I FOR ATIO controller is permitted to start operating. As the voltage on RUN/SS increases from 1.5V to 3.5V, the internal current limit is increased from 20mV/R SENSE The output current limit ramps up slowly, ...
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U U APPLICATIO S I FOR ATIO increasing current draw with increasing voltage. The EAIN pin should be artificially held 70% above its nominal operating level of 0.6V, or 0.42V in order to prevent the IC from “folding back” the ...
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LTC3732 U U APPLICATIO S I FOR ATIO master’s frequency. A voltage of 1.7V or below applied to the master oscillator’s PLLFLTR pin is recommended in order to meet this requirement. The resultant operating frequency will be approximately 550kHz for ...
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U U APPLICATIO S I FOR ATIO loop feedback factor gain and phase. An output current pulse of 20% to 80% of full load current having a rise time of <2 s will produce output voltage and I that will ...
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LTC3732 U U APPLICATIO S I FOR ATIO Using commonly available value results in 34% ripple current. The worst-case output ripple for the three stages operating in parallel will be less than 11% of the ...
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U U APPLICATIO S I FOR ATIO – Are the SENSE and SENSE printed circuit traces for each channel routed together with minimum PC trace spacing? The filter capacitors between SENSE for each channel should be as close ...
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LTC3732 U U APPLICATIO S I FOR ATIO Figure 11 illustrates all branch currents in a three-phase switching regulator. It becomes very clear after studying the current waveforms why it is critical to keep the high switching current paths to ...
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U U APPLICATIO S I FOR ATIO The output ripple current is reduced significantly when compared to the single phase solution using the same inductance value because the V OUT term from the stages that has their bottom MOSFETs on ...
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LTC3732 U U APPLICATIO S I FOR ATIO Total of all three main MOSFET’s AC loss 1000 MAIN 400 5 ...
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... DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 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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... Synchronous Step-Down Controller LTC3731 3-Phase 600kHz Synchronous Step-Down Controller LTC3778 Optional R Current Mode Synchronous SENSE Step-Down Controller trademark of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ...