LT3688 ABSOLUTE MAXIMUM RATINGS(Note 1) VIN, EN/UVLO, CONFIG Voltage (Note 2) ...36V Operating Junction Temperature Range (Note 3) BST Voltage ..55V LT3688E, LT3688I ..–40°C to 125°C BST above SW Voltage ...30V LT3688H ..–40°C to 150°C BIAS Voltage ...30V Maximum Junction Temperature WDE, WDI, RST, WDO Voltage ...6V LT3688E, LT3688I ... 125°C FB, RT , SYNC, RUN/SS Voltage ..6V LT3688H ... 150°C CWDT , CPOR Voltage ..3V Storage Temperature Range ...–65°C to 150°C Lead Temperature (Soldering, 10 sec) FE Package ... 300°C PIN CONFIGURATION TOP VIEW TOP VIEW FB1 1 24 EN/UVLO RUN/SS1 2 23 SYNC WDT POR1 POR2 C C BIAS C WDI WDE BST1 3 22 RT 24 23 22 21 20 19 SW1 4 21 C WDO WDT RT 1 18 DA1 5 20 C SYNC 2 17 RST1 POR1 RST2 V 6 19 EN/UVLO 3 16 IN BIAS 25 25 GND FB1 4 GND 15 FB2 CONFIG 7 18 CPOR2 RUN/SS1 5 14 RUN/SS2 DA2 8 17 WDI BST1 6 13 BST2 SW2 9 16 WDE BST2 10 15 WDO 7 8 9 10 11 12 IN RUN/SS2 11 14 RST1 SW1 DA1 V DA2 SW2 FB2 12 13 RST2 CONFIG FE PACKAGE UF PACKAGE 24-LEAD PLASTIC TSSOP 24-LEAD (4mm × 4mm) PLASTIC QFN θJA = 38°C/W θJA = 37°C/W EXPOSED PAD (PIN 25) IS GND, MUST BE ELECTRICALLY CONNECTED TO PCB EXPOSED PAD (PIN 25) IS GND, MUST BE ELECTRICALLY CONNECTED TO PCB ORDER INFORMATION LEAD FREE FINISHTAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGE LT3688EFE#PBF LT3688EFE#TRPBF LT3688FE 24-Lead Plastic TSSOP –40°C to 125°C LT3688IFE#PBF LT3688IFE#TRPBF LT3688FE 24-Lead Plastic TSSOP –40°C to 125°C LT3688HFE#PBF LT3688HFE#TRPBF LT3688FE 24-Lead Plastic TSSOP –40°C to 150°C LT3688EUF#PBF LT3688EUF#TRPBF 3688 24-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C LT3688IUF#PBF LT3688IUF#TRPBF 3688 24-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is 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/ 3688f 2