LT3990/LT3990-3.3/LT3990-5 62V, 350mA Step-Down Regulator with 2.5A Quiescent Current and Integrated Diodes FEATURES DESCRIPTION n Low Ripple Burst Mode Operation The LT 3990 is an adjustable frequency monolithic buck 2.5A I at 12V to 3.3V switching regulator that accepts a wide input voltage Q IN OUT Output Ripple < 5mV range up to 62V, and consumes only 2.5A of quiescent P-P n Wide Input Voltage Range: 4.2V to 62V Operating current. A high efficiency switch is included on the die n Adjustable Switching Frequency: 200kHz to 2.2MHz along with the catch diode, boost diode, and the neces- n Integrated Boost and Catch Diodes sary oscillator, control and logic circuitry. Low ripple Burst n 350mA Output Current Mode operation maintains high efficiency at low output n Fixed Output Voltages: 3.3V, 5V currents while keeping the output ripple below 5mV in a 2A I at 12V typical application. Current mode topology is used for fast Q IN n Accurate Programmable Undervoltage Lockout transient response and good loop stability. A catch diode n FMEA Fault Tolerant (MSOP Package) current limit provides protection against shorted outputs Output Stays at or Below Regulation Voltage During and overvoltage conditions. An accurate programmable Adjacent Pin Short or When a Pin is Left Floating undervoltage lockout feature is available, producing a low n Low Shutdown Current: I = 0.7A shutdown current of 0.7A. A power good flag signals when Q n Internal Sense Limits Catch Diode Current V reaches 90% of the programmed output voltage. The OUT n Power Good Flag LT3990 is available in small, thermally enhanced 16-pin n Small, Thermally Enhanced 16-Pin MSOP MSOP and 3mm 3mm DFN packages. and (3mm 3mm) DFN Packages L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIONS n Automotive Battery Regulation n Power for Portable Products n Industrial Supplies TYPICAL APPLICATION Power Loss 1000 V = 12V IN 5V Step-Down Converter 100 V IN 6.5V TO 62V 0.22F V BOOST 10 IN LT3990-5 33H V OUT OFF ON EN/UVLO SW 5V 1 350mA PG BD RT V 0.1 2.2F 22F OUT GND 374k 0.01 3990 TA01a f = 400kHz 0.001 0.01 0.1 1 10 100 LOAD CURRENT (mA) 3990 TA01b 3990fa 1 POWER LOSS (mW)LT3990/LT3990-3.3/LT3990-5 ABSOLUTE MAXIMUM RATINGS (Note 1) V , EN/UVLO Voltage ...............................................62V Operating Junction Temperature Range (Note 2) IN BOOST Pin Voltage ...................................................75V LT3990E/LT3990E-X ........................... 40C to 125C BOOST Pin Above SW Pin .........................................30V LT3990I/LT3990I-X ............................ 40C to 125C FB/V , RT Voltage ....................................................6V LT3990H/LT3990H-X .......................... 40C to 150C OUT PG, BD Voltage .........................................................30V Storage Temperature Range ................... 65C to 150C Lead Temperature (Soldering, 10 sec) MS Only ............................................................ 300C PIN CONFIGURATION TOP VIEW TOP VIEW FB/V * 1 16 RT OUT FB/V * 2 15 NC FB 10 RT OUT 1 NC 3 14 PG EN/UVLO 2 9 PG EN/UVLO 4 17 13 BD 11 NC 5 12 NC GND V 3 8 BD IN GND V 6 11 BOOST IN GND 4 7 BOOST NC 7 10 NC GND 8 9 SW GND 5 6 SW MSE PACKAGE 16-LEAD PLASTIC MSOP DD PACKAGE 10-LEAD (3mm 3mm) PLASTIC DFN = 40C/W, = 10C/W JA JC EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB = 45C/W, = 10C/W JA JC EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB *FB FOR LT3990, V FOR LT3990-3.3, LT3990-5 OUT ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3990EDD PBF LT3990EDD TRPBF LFWJ 40C to 125C 10-Lead (3mm 3mm) Plastic DFN LT3990IDD PBF LT3990IDD TRPBF LFWJ 40C to 125C 10-Lead (3mm 3mm) Plastic DFN LT3990EMSE PBF LT3990EMSE TRPBF 3990 16-Lead Plastic MSOP 40C to 125C LT3990IMSE PBF LT3990IMSE TRPBF 3990 16-Lead Plastic MSOP 40C to 125C LT3990HMSE PBF LT3990HMSE TRPBF 3990 16-Lead Plastic MSOP 40C to 150C LT3990EMSE-3.3 PBF LT3990EMSE-3.3 TRPBF 399033 16-Lead Plastic MSOP 40C to 125C LT3990IMSE-3.3 PBF LT3990IMSE-3.3 TRPBF 399033 16-Lead Plastic MSOP 40C to 125C LT3990HMSE-3.3 PBF LT3990HMSE-3.3 TRPBF 399033 16-Lead Plastic MSOP 40C to 150C LT3990EMSE-5 PBF LT3990EMSE-5 TRPBF 39905 16-Lead Plastic MSOP 40C to 125C LT3990IMSE-5 PBF LT3990IMSE-5 TRPBF 39905 16-Lead Plastic MSOP 40C to 125C LT3990HMSE-5 PBF LT3990HMSE-5 TRPBF 39905 16-Lead Plastic MSOP 40C to 150C 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: