LTC3813 100V Current Mode Synchronous Step-Up Controller FEATURES DESCRIPTION n High Output Voltages: Up to 100V The LTC3813 is a synchronous step-up switching regulator n Large 1 Gate Drivers controller that can generate output voltages up to 100V. n No Current Sense Resistor Required The LTC3813 uses a constant off-time peak current control n Dual N-Channel MOSFET Synchronous Drive architecture with accurate cycle-by-cycle current limit, n 0.5% 0.8V Voltage Reference without requiring a sense resistor. n Fast Transient Response A precise internal reference provides 0.5% DC accuracy. n Programmable Soft-Start A high bandwidth (25MHz) error ampli er provides very n Generates 10V Driver Supply from Input Supply fast line and load transient response. Large 1 gate drivers n Synchronizable to External Clock allow the LTC3813 to drive multiple MOSFETs for higher n Power Good Output Voltage Monitor current applications. The operating frequency is selected n Adjustable Off-Time/Frequency: t < 100ns OFF(MIN) by an external resistor and is compensated for variations n Adjustable Cycle-by-Cycle Current Limit in V and can also be synchronized to an external clock IN n Programmable Undervoltage Lockout for switching-noise sensitive applications. A shutdown pin n Output Overvoltage Protection allows the LTC3813 to be turned off, reducing the supply n 28-Pin SSOP Package current to 240A. PARAMETER LTC3813 LTC3814-5 APPLICATIONS Maximum V 100V 60V OUT n 24V Fan Supplies MOSFET Gate Drive 6.35V to 14V 4.5V to 14V n + 48V Telecom and Base Station Power Supplies INTV UV 6.2V 4.2V CC n Networking Equipment, Servers INTV UV 6V 4V CC n Automotive and Industrial Control Systems L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 5847554, 6304066, 6476589, 6580258, 6677210, 6774611. TYPICAL APPLICATION High Ef ciency High Voltage Step-Up Converter Ef ciency vs Load Current 50k 100 V = 36V 500k IN V V OUT I NDRV IN OFF 10V TO 40V V = 24V + IN 95 PGOOD BOOST 10H 22F V = 12V LTC3813 IN V TG RNG M1 0.1F Si7850DP V 90 SYNC OUT 1000pF SW 50V/5A EXTV CC SS DRV CC 85 SHDN D1 INTV CC 30.9k MBR1100 + + SENSE I TH 270F M2 0.01F 100k BG 2x Si7850DP 80 V 04123 5 FB 2x SENSE LOAD (A) 100pF 3813 TA01b SGND BGRTN 499 1F 3813 TA01 3813fb 1 EFFICIENCY (%)LTC3813 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) TOP VIEW Supply Voltages I 1 28 BOOST INTV , DRV ....................................... 0.3V to 14V OFF CC CC NC 2 27 TG (DRV - BGRTN), (BOOST - SW).......... 0.3V to 14V CC NC 3 26 SW BOOST ................................................. 0.3V to 114V + V 4 25 SENSE OFF BGRTN ........................................................ 5V to 0V V 5 24 NC RNG EXTV .................................................. 0.3V to 15V CC PGOOD 6 23 NC (NDRV - INTV ) Voltage ........................... 0.3V to 10V CC SYNC 7 22 NC + SW, SENSE Voltage ................................... 1V to 100V I 8 21 SENSE TH I Voltage .............................................. 0.3V to 100V OFF V 9 20 BGRTN FB SS Voltage ................................................... 0.3V to 5V PLL/LPF 10 19 BG PGOOD Voltage ............................................ 0.3V to 7V SS 11 18 DRV CC V , V , SYNC, SHDN, SGND 12 17 INTV RNG OFF CC UVIN Voltages ........................................ 0.3V to 14V SHDN 13 16 EXTV CC UVIN PLL/LPF, FB Voltages ................................. 0.3V to 2.7V 14 15 NDRV TG, BG, INTV , EXTV RMS Currents .................50mA CC CC G PACKAGE 28-LEAD PLASTIC SSOP Operating Temperature Range (Note 2) T = 125C, = 100C/W JMAX JA LTC3813E ............................................. 40C to 85C LTC3813I............................................ 40C to 125C Junction Temperature (Notes 3, 7)........................ 125C Storage Temperature Range ................... 65C to 150C Lead Temperature (Soldering, 10 sec) .................. 300C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3813EG PBF LTC3813EG TRPBF LTC3813EG 28-Lead Plastic SSOP 40C to 85C LTC3813IG PBF LTC3813IG TRPBF LTC3813IG 28-Lead Plastic SSOP 40C to 125C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based nish parts. For more information on lead free part marking, go to: