POWER LOSS (W) LTC3803-5 Constant Frequency Current Mode Flyback DC/DC Controller in ThinSOT FEATURES DESCRIPTION n V and V Limited Only by External Components The LTC 3803-5 is a constant frequency current mode IN OUT n 4.8V Undervoltage Lockout Threshold yback controller optimized for driving N-channel MOSFETs n Operating Junction Temperature from 55C to in high input voltage applications. The LTC3803-5 operates 150C from inputs as low as 5V. Constant frequency operation n Adjustable Slope Compensation is maintained down to very light loads, resulting in less n Internal Soft-Start low frequency noise generation over a wide range of load n Constant Frequency 200kHz Operation currents. Slope compensation can be programmed with n 1.5% Reference Accuracy an external resistor. n Current Mode Operation for Excellent Line and Load The LTC3803-5 provides 1.5% output voltage accuracy Transient Response and consumes only 240A of quiescent current. Ground- n No Minimum Load Requirement referenced current sensing allows LTC3803-5-based con- n Low Quiescent Current: 240A verters to accept input supplies beyond the LTC3803-5s n Low Pro le (1mm) SOT-23 Package absolute maximum V . For simplicity, the LTC3803-5 can CC be powered from a high V through a resistor, due to its IN internal shunt regulator. An internal undervoltage lockout APPLICATIONS shuts down the IC when the input voltage is too low to n 42V and 12V Automotive Power Supplies provide suf cient gate drive to the external MOSFET. n Telecom Power Supplies n Auxiliary/Housekeeping Power Supplies The LTC3803-5 is available in a low pro le (1mm) 6-lead n Power Over Ethernet SOT-23 (ThinSOT) package. L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks and ThinSOT and No R are trademarks of Linear Technology Corporation. All other SENSE trademarks are the property of their respective owners. TYPICAL APPLICATION Ef ciency and Power Loss Dual Output Wide Input Range Converter vs Output Power 10MQ100N VPH5-0155 V 13V/0.3A IN 90 3.0 V = 8V 6V TO 50V 20mA MIN IN 1F LOAD 100V 22k 85 2.5 PDZ6.8B 3 V = 12V IN 22F 10V MMBTA42 80 2.0 1F V = 24V IN 10nF PHM25NQ10T 100V LTC3803-5 7.5k 75 1.5 1F I /RUN NGATE TH 100V GND V 6.5V/1.2A CC 70 1.0 4.7k V SENSE FB B3100 V = 48V 47F IN 8.06k 10V 0.012 65 0.5 0.1F V = 12V IN 57.6k 60 0 02 4 68 10 12 ALL CAPACITORS ARE X7R, TDK OUTPUT POWER (W) 38035 TA01 38035 TA01b 38035fd 1 EFFICIENCY (%)LTC3803-5 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) V to GND (Current Fed) ..................... 25mA into V * CC CC NGATE Voltage .......................................... 0.3V to V CC TOP VIEW V , I /RUN Voltages............................... 0.3V to 3.5V FB TH I /RUN 1 6 NGATE SENSE Voltage ............................................ 0.3V to 1V TH GND 2 5 V CC NGATE Peak Output Current (<10s) ......................... 1A V 3 4 SENSE FB Operating Junction Temperature Range (Notes 2, 3) LTC3803E-5 ....................................... 40C to 125C S6 PACKAGE 6-LEAD PLASTIC TSOT-23 LTC3803I-5 ........................................ 40C to 125C T = 150C, = 192C/W JMAX JA LTC3803H-5 (Note 3) ......................... 40C to 150C LTC3803MP-5 (Note 3) ...................... 55C to 150C Storage Temperature Range ...................65C to 150C Lead Temperature (Soldering, 10 sec) .................. 300C *LTC3803-5 internal clamp circuit self regulates V voltage to 8.1V. CC ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3803ES6-5 PBF LTC3803ES6-5 TRPBF LTBPF 6-Lead Low Pro le (1mm) SOT-23 40C to 125C LTC3803IS6-5 PBF LTC3803IS6-5 TRPBF LTBMH 6-Lead Low Pro le (1mm) SOT-23 40C to 125C LTC3803HS6-5 PBF LTC3803HS6-5 TRPBF LTBMH 6-Lead Low Pro le (1mm) SOT-23 40C to 150C LTC3803MPS6-5 PBF LTC3803MPS6-5 TRPBF LTBMH 6-Lead Low Pro le (1mm) SOT-23 55C to 150C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC3803ES6-5 LTC3803ES6-5 TR LTBPF 6-Lead Low Pro le (1mm) SOT-23 40C to 125C LTC3803IS6-5 LTC3803IS6-5 TR LTBMH 6-Lead Low Pro le (1mm) SOT-23 40C to 125C LTC3803HS6-5 LTC3803HS6-5 TR LTBMH 6-Lead Low Pro le (1mm) SOT-23 40C to 150C LTC3803MPS6-5 LTC3803MPS6-5 TR LTBMH 6-Lead Low Pro le (1mm) SOT-23 55C to 150C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. For more information on lead free part marking, go to: