LT3478/LT3478-1 WWWUUWUABSOLUTE AXI URATI GSPACKAGE/ORDER I FOR ATIO(Note 1) TOP VIEW SW ..42V V SW 1 16 SS OUT, LED ..42V V SW 2 15 RT IN, VS, VL, ⎯S⎯H⎯D⎯N (Note 5) ...36V V 3 14 PWM PWM ...15V IN V 4 13 CTRL2 CTRL1, 2 ...6V S 17 L 5 12 CTRL1 SS, RT, VC, VREF, OVPSET ..2V V 6 11 OUT SHDN Operating Junction Temperature Range LED 7 10 VREF (Notes 2, 3, 4) .. –40°C to 125°C OVPSET 8 9 VC Storage Temperature Range ... –65°C to 150°C FE PACKAGE Lead Temperature (Soldering, 10 Sec) .. 300°C 16-LEAD PLASTIC TSSOP TJMAX = 125°C, θJA = 35°C/W EXPOSED PAD (PIN 17) IS PGND, MUST BE SOLDERED TO PCB. ORDER PART NUMBER FE PART MARKING LT3478EFE 3478FE LT3478EFE-1 3478FE-1 LT3478IFE 3478FE LT3478IFE-1 3478FE-1 Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/ Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. TheELECTRICAL CHARACTERISTICS ● denotes the specifi cations which apply over the full operatingtemperature range, otherwise specifi cations are at TA = 25°C. SW = open, VIN = VS = L = VOUT = ⎯ S ⎯ H ⎯ D ⎯ N = 2.7V, LED = open, SS = open, PWM = CTRL1, CTRL2 = 1.25V, VREF = open, VC = open, RT = 31.6k.PARAMETERCONDITIONSMINTYPMAXUNITS Minimum Operating Voltage (Rising) ● 2.4 2.8 V Operational Input Voltage VS 2.8 36 V VIN (Note 5) 2.8 36 V VIN Quiescent Current VC = 0V (No Switching) 6.1 mA VIN Shutdown Current ⎯S⎯H⎯D⎯N = 0V 3 6 µA ⎯S⎯H⎯D⎯N Pin Threshold (VSD_µp) (Micropower) ● 0.1 0.4 0.7 V ⎯S⎯H⎯D⎯N Pin Threshold (VSD_UVLO) (Switching) 1.3 1.4 1.5 V ⎯S⎯H⎯D⎯N Pin Current ⎯S⎯H⎯D⎯N = VSD_UVLO – 50mV 8 10 12 µA ⎯S⎯H⎯D⎯N = VSD_UVLO + 50mV 0 µA VREF Voltage I(VREF) = 0µA, VC = 0V ● 1.213 1.240 1.263 V VREF Line Regulation I(VREF) = 0µA, 2.7V < VIN < 36V 0.005 0.015 %/V VREF Load Regulation 0 < I(VREF) < 100µA (Max) 8 12 mV Frequency: fOSC 200kHz RT = 200k 0.18 0.2 0.22 MHz Frequency: fOSC 1MHz RT = 31.6k ● 0.88 1.12 MHz 34781f 2