LTC4449 High Speed Synchronous N-Channel MOSFET Driver FEATURES DESCRIPTION n 4V to 6.5V V Operating Voltage The LTC 4449 is a high frequency gate driver that CC n 38V Maximum Input Supply Voltage is designed to drive two N-Channel MOSFETs in a n Adaptive Shoot-Through Protection synchronous DC/DC converter. The powerful rail-to-rail n Rail-to-Rail Output Drivers driver capability reduces switching losses in MOSFETs n 3.2A Peak Pull-Up Current with high gate capacitance. n 4.5A Peak Pull-Down Current The LTC4449 features a separate supply for the input logic n 8ns TG Rise Time Driving 3000pF Load to match the signal swing of the controller IC. If the input n 7ns TG Fall Time Driving 3000pF Load signal is not being driven, the LTC4449 activates a shutdown n Separate Supply to Match PWM Controller mode that turns off both external MOSFETs. The input logic n Drives Dual N-Channel MOSFETs signal is internally level-shifted to the bootstrapped supply, n Undervoltage Lockout which functions at up to 42V above ground. n Low Pro le (0.75mm) 2mm 3mm DFN Package The LTC4449 contains undervoltage lockout circuits on APPLICATIONS both the driver and logic supplies that turn off the external MOSFETs when an undervoltage condition is present. An n Distributed Power Architectures adaptive shoot-through protection feature is also built-in n High Density Power Modules to prevent the power loss resulting from MOSFET cross- L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear conduction current. Technology Corporation. All other trademarks are the property of their respective owners. The LTC4449 is available in the 2mm 3mm DFN package. TYPICAL APPLICATION Synchronous Buck Converter Driver LTC4449 Driving 3000pF Capacitive Loads V CC 4V TO 6.5V V CC INPUT (IN) V IN BOOST 5V/DIV TO 38V V LOGIC LTC4449 TOP GATE TG (TG - TS) 5V/DIV TS V OUT PWM IN BG GND BOTTOM GATE (BG) 5V/DIV 4449 TA01a 4449 TA01b 10ns/DIV 4449fa 1LTC4449 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) Supply Voltage TOP VIEW V ...................................................... 0.3V to 7V LOGIC TG 1 8 BOOST V ........................................................... 0.3V to 7V CC TS 2 7 V CC 9 BOOST TS ............................................. 0.3V to 7V BG 6 V 3 LOGIC BOOST Voltage .......................................... 0.3V to 42V GND 5 IN 4 TS ................................................................. 5V to 38V DCB PACKAGE IN Voltage .................................................... 0.3V to 7V 8-LEAD (2mm s 3mm) PLASTIC DFN = 64C/W, = 10.6C/W JA JC Driver Output TG (with Respect to TS) ......... 0.3V to 7V EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB Driver Output BG .......................................... 0.3V to 7V Operating Junction Temperature Range (Notes 2, 3) ............................................40C to 125C Storage Temperature Range ...................65C to 150C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC4449EDCB PBF LTC4449EDCB TRPBF LFKC 8-Lead (2mm 3mm) Plastic DFN 40C to 125C LTC4449IDCB PBF LTC4449IDCB TRPBF LFKC 40C to 125C 8-Lead (2mm 3mm) Plastic DFN Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *Temperature grades are identi ed by a label on the shipping container. Consult LTC Marketing for information on lead based nish parts. For more information on lead free part marking, go to: