LT3508 ABSOLUTE MAXIMUM RATINGS (Notes 1, 7) VIN Pin Voltage ..(–0.3V), 40V Storage Temperature Range BOOST Pin Voltage ...60V QFN .. –65°C to 150°C BOOST Above SW Voltage ..30V TSSOP ... –65°C to 150°C SHDN, PG Voltage ...40V Lead Temperature (Soldering, 10 sec) TRACK/SS, FB, RT/SYNC, VC Voltage ..6V TSSOP .. 300°C Operating Junction Temperature Range (Note 2) LT3508E ... –40°C to 125°C LT3508I .. –40°C to 125°C LT3508H .. –40°C to 150°C PIN CONFIGURATION TOP VIEW TOP VIEW C1 T/SYNC C2 V PG1 R SHDN PG2 V TRACK/SS1 1 16 FB1 24 23 22 21 20 19 BOOST1 2 15 VC1 FB1 1 18 FB2 SW1 3 14 PG1 TRACK/SS1 2 17 TRACK/SS2 V 4 IN1 13 RT/SYNC 17 GND 3 25 16 GND V 5 GND IN2 12 SHDN GND GND 4 15 GND SW2 6 11 PG2 GND 5 14 GND BOOST2 7 10 VC2 GND 6 13 GND TRACK/SS2 8 9 FB2 7 8 9 10 11 12 FE PACKAGE IN1 IN2 SW1 V V SW2 16-LEAD PLASTIC TSSOP θ BOOST1 BOOST2 JA = 40°C/W, θJC = 10°C/W UF PACKAGE EXPOSED PAD (PIN 17) IS GND AND MUST BE SOLDERED TO PCB 24-LEAD (4mm × 4mm) PLASTIC QFN θJA = 40°C/W, θJC = 10°C/W EXPOSED PAD (PIN 25) IS GND AND MUST BE SOLDERED TO PCB ORDER INFORMATIONLEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGE LT3508EFE#PBF LT3508EFE#TRPBF 3508FE 16-Lead Plastic TSSOP –40°C to 125°C LT3508IFE#PBF LT3508IFE#TRPBF 3508FE 16-Lead Plastic TSSOP –40°C to 125°C LT3508HFE#PBF LT3508HFE#TRPBF 3508HFE 16-Lead Plastic TSSOP –40°C to 150°C LT3508EUF#PBF LT3508EUF#TRPBF 3508 24-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C LT3508IUF#PBF LT3508IUF#TRPBF 3508 24-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C LT3508HUF#PBF LT3508HUF#TRPBF 3508H 24-Lead (4mm × 4mm) Plastic QFN –40°C to 150°C Consult LTC Marketing for parts specifi ed with wider operating temperature ranges.*Temperature grades are identifi ed by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifi cations, go to: http://www.linear.com/tapeandreel/ 3508fd 2 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS BLOCK DIAGRAM OPERATION APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS