LTC3857 ABSOLUTE MAXIMUM RATINGSPIN CONFIGURATION(Note 1) TOP VIEW Input Supply Voltage (VIN) ... –0.3V to 40V + Topside Driver Voltages BOOST1, BOOST2 ... –0.3V to 46V FB1 SENSE1 V I TH1 TRACK/SS1 I LIM PGOOD1 TG1 SW1 Switch Voltage (SW1, SW2) .. –5V to 40V 32 31 30 29 28 27 26 25 SENSE1– 1 24 BOOST1 PLLIN/MODE, (BOOST1-SW1), (BOOST2-SW2), FREQ 2 23 BG1 INTVCC .. –0.3V to 6V PHASMD 3 22 VIN RUN1, RUN2 .. –0.3V to 8V CLKOUT 4 21 PGND 33 Maximum Current Sourced into Pin PLLIN/MODE 5 SGND 20 EXTVCC from Source >8V...100μA SGND 6 19 INTVCC SENSE1+, SENSE2+, SENSE1– RUN1 7 18 BG2 SENSE2– Voltages .. –0.3V to 28V RUN2 8 17 BOOST2 FREQ Voltages ... –0.3V to INTV 9 10 11 12 13 14 15 16 CC – + I FB2 LIM, PHASMD Voltages ... –0.3V to INTVCC V I TH2 TG2 SW2 EXTVCC .. –0.3V to 14V SENSE2 SENSE2 PGOOD2 TRACK/SS2 ITH1, ITH2,VFB1, VFB2 Voltages .. –0.3V to 6V UH PACKAGE 32-LEAD (5mm s 5mm) PLASTIC QFN PGOOD1, PGOOD2 Voltages ... –0.3V to 6V TJMAX = 125°C, θJA = 34°C/W TRACK/SS1, TRACK/SS2 Voltages .. –0.3V to 6V EXPOSED PAD (PIN 33) IS SGND, MUST BE SOLDERED TO PCB Operating Junction Temperature Range (Note 2) .. –40°C to 125°C Maximum Junction Temperature (Note 3) .. 125°C Storage Temperature Range ... –65°C to 150°C ORDER INFORMATIONLEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGE LTC3857EUH#PBF LTC3857EUH#TRPBF 3857 32-Lead (5mm × 5mm) Plastic QFN –40°C to 125°C LTC3857IUH#PBF LTC3857IUH#TRPBF 3857 32-Lead (5mm × 5mm) Plastic QFN –40°C to 125°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ ELECTRICAL CHARACTERISTICSThe l denotes the specifications which apply over the full operating junctiontemperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = 12V, VRUN1,2 = 5V, EXTVCC = 0V, unless otherwise noted.SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITS VIN Input Supply Operating Voltage Range 4 38 V VFB1,2 Regulated Feedback Voltage (Note 4) ITH1,2 Voltage = 1.2V –40°C to 125°C l 0.788 0.800 0.812 V –40°C to 85°C 0.792 0.800 0.808 V IFB1,2 Feedback Current (Note 4) ±5 ±50 nA VREFLNREG Reference Voltage Line Regulation (Note 4) VIN = 4.5V to 38V 0.002 0.02 %/V 3857fd 2 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS FUNCTIONAL DIAGRAM OPERATION APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS