LTC7803 40V Low IQ, 3MHz Synchronous Step-Down …

1 LTC78031 Rev. AFor more information FeedbackTYPICAL APPLICATION FEATURESDESCRIPTION40V Low IQ, 3 MHz Synchronous Step-Down Controller with Spread SpectrumThe LT C 7803 is a high performance, 100% Duty Cycle Capable, Synchronous Step-Down DC/DC switching regulator controller that drives an all N-channel power MOSFET stage. Synchronous rectification increases effi-ciency, reduces power losses and eases thermal require-ments. A constant frequency current mode architecture allows a phase-lockable switching frequency of up to 3 MHz.

2 The LTC7803 operates from a wide to 40V input supply range. The very low no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP com-pensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light LTC7803 additionally features spread spectrum oper-ation which significantly reduces the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interfer-ence (EMI) standards.

3 APPLICATIONS nAutomotive and Transportation nIndustrial nMilitary/Avionics nTelecommunicationsAll registered trademarks and trademarks are the property of their respective owners. Protected by Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258. nLow Operating IQ: 12 A (14V VIN to VOUT) nWide Input Voltage Range: to 40V nOutput Voltage Up to 40V nSpread spectrum Operation nRSENSE or DCR Current Sensing nPassThru /100% Duty Cycle Capable nProgrammable Fixed Frequency (100kHz to 3 MHz) nPhase-Lockable Frequency (100kHz to 3 MHz) nSelectable Continuous, Pulse-Skipping, or Low Ripple Burst Mode Operation at Light Loads nLow Shutdown IQ.

4 A nThermally Enhanced 16-Pin 3mm 3mm QFN and MSOP Packages nAEC-Q100 Qualification in TO F HTRACK//SSITHMODEFREQGND7803 TA01aLTC7803 RUNVINBOOSTSWBGINTVCCSENSE+SENSE TGPLLIN/SPREADVFBEXTVCC56 F 2100 F F1m F+470 F+ 2 2 VOUT = MODE OPERATIONFIGURE 11 CIRCUITVIN = 12 VVIN = 24 VVIN = 36 VOUTPUT CURRENT (A) (%)Ef ciency vs Output Current7803 TA01bEfficiency vs Output CurrentHigh Efficiency Wide Input Range 375kHz Step-Down RegulatorLTC78032 Rev. AFor more information CONFIGURATIONABSOLUTE MAXIMUM RATINGSI nput Supply Voltage (VIN).

5 To 40 VBOOST .. to 46 VSW .. 5V to 40 VRUN .. to 40 VSENSE+, SENSE .. to 40 VEXTVCC Voltage .. to 30 VINTVCC, (BOOST-SW) .. to 6 VTRACK/SS, FREQ .. to 6V(Note 1)12345678 TRACK/SSSENSE+SENSE VFBITHRUNFREQPLLIN/SPREAD161514131211109 SWTGBOOSTBGVINEXTVCCINTVCCMODETOP VIEWMSE PACKAGE16-LEAD PLASTIC MSOPTJMAX = 125 C, JA = 40 C/W, JC = 10 C/WEXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB17 GND161514135678 TOP VIEW17 GNDUD PACKAGE16-LEAD (3mm 3mm) PLASTIC QFNTJMAX = 125 C, JA = 68 C/W, JC = C/WEXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB91011124321 TGSWTRACK/SSSENSE+INTVCCMODEPLLIN/SPREAD FREQBOOSTBGVINEXTVCCSENSE VFBITHRUNITH.

6 To 2 VPLLIN/SPREAD, MODE, VFB .. to 6 VBG, TG ..(Note 9)Operating Junction Temperature Range (Note 2,8) LTC7803E, LTC7803I .. 40 C to 125 C LTC7803H, LTC7803J .. 40 C to 150 C Storage Temperature Range .. 65 C to 150 CLTC78033 Rev. AFor more information INFORMATIONLEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGELTC7803 EMSE#PBFLTC7803 EMSE#TRPBF780316-Lead Plastic MSOP 40 C to 125 CLTC7803 IMSE#PBFLTC7803 IMSE#TRPBF780316-Lead Plastic MSOP 40 C to 125 CLTC7803 JMSE#PBFLTC7803 JMSE#TRPBF780316-Lead Plastic MSOP 40 C to 150 CLTC7803 HMSE#PBFLTC7803 HMSE#TRPBF780316-Lead Plastic MSOP 40 C to 150 CLTC7803 EUD#PBFLTC7803 EUD#TRPBFLHGT16-Lead (3mm 3mm)

7 Plastic QFN 40 C to 125 CLTC7803 IUD#PBFLTC7803 IUD#TRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 125 CLTC7803 JUD#PBFLTC7803 JUD#TRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 150 CLTC7803 HUD#PBFLTC7803 HUD#TRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 150 CAUTOMOTIVE PRODUCTS** LTC7803 EMSE#WPBFLTC7803 EMSE#WTRPBF780316-Lead Plastic MSOP 40 C to 125 CLTC7803 IMSE#WPBFLTC7803 IMSE#WTRPBF780316-Lead Plastic MSOP 40 C to 125 CLTC7803 JMSE#WPBFLTC7803 JMSE#WTRPBF780316-Lead Plastic MSOP 40 C to 150 CLTC7803 HMSE#WPBFLTC7803 HMSE#WTRPBF780316-Lead Plastic MSOP 40 C to 150 CLTC7803 EUD#WPBFLTC7803 EUD#WTRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 125 CLTC7803 IUD#WPBFLTC7803 IUD#WTRPBFLHGT16-Lead (3mm 3mm)

8 Plastic QFN 40 C to 125 CLTC7803 JUD#WPBFLTC7803 JUD#WTRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 150 CLTC7803 HUD#WPBFLTC7803 HUD#WTRPBFLHGT16-Lead (3mm 3mm) Plastic QFN 40 C to 150 CContact the factory for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping and reel specifications. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.**Versions of this part are available with controlled manufacturing to support the quality and reliability requirements of automotive applications.

9 These models are designated with a #W suffix. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these CHARACTERISTICSSYMBOLPARAMETERCONDITIONS MINTYPMAXUNITSI nput SupplyVINI nput Supply Operating Current in RegulationFront Page Circuit, 14V to No Load12 AController OperationVOUTO utput Voltage Operating Feedback Voltage(Note 4) VIN = to 40V, ITH Voltage = to 0 C to 85 C, All Grades l V VFeedback Current(Note 4)

10 5 50nAFeedback Overvoltage Protection ThresholdMeasured at VFB Relative to Regulated VFB71013%gmTransconductance Amplifier gm(Note 4) ITH = , Sink/Source = 5 A2mmhoVSENSE(MAX)Maximum Current Sense ThresholdVFB = , VSENSE = The l denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25 C, VIN = 12V, RUN = 12V, EXTVCC = 0V, unless otherwise noted.