LT8304/LT8304-1 100V Micropower IN No-Opto Isolated Flyback Converter with 150V/2A Switch FEATURES DESCRIPTION n 3V to 100V Input Voltage Range The LT 8304/LT8304-1 are monolithic micropower iso- n lated flyback converters. By sampling the isolated output 2A, 150V Internal DMOS Power Switch n voltage directly from the primary-side flyback waveform, Low Quiescent Current: n the parts require no third winding or opto-isolator for 116A in Sleep Mode n regulation. The output voltage is programmed with two 390A in Active Mode n external resistors and a third optional temperature com- Quasi-Resonant Boundary Mode Operation at pensation resistor. Boundary mode operation provides a Heavy Load n small magnetic solution with excellent load regulation. Low Low Ripple Burst Mode Operation at Light Load ripple Burst Mode operation maintains high efficiency at n Minimum Load < 0.5% (Typ) of Full Output light load while minimizing the output voltage ripple. A 2A, n No Transformer Third Winding or Opto-Isolator 150V DMOS power switch is integrated along with all the Required for Output Voltage Regulation high voltage circuitry and control logic into a thermally n Accurate EN/UVLO Threshold and Hysteresis enhanced 8-lead SO package. n Internal Compensation and Soft-Start n Temperature Compensation for Output Diode The LT8304/LT8304-1 operate from an input voltage range n Output Short-Circuit Protection of 3V to 100V and deliver up to 24W of isolated output n Thermally Enhanced 8-Lead SO Package power. The high level of integration and the use of boundary and low ripple Burst Mode operation result in a simple to use, low component count, and high efficiency applica- APPLICATIONS tion solution for isolated power delivery. The LT8304-1 is n Isolated Automotive, Industrial, Medical, Telecom specially optimized for high step-up output applications. Power Supplies L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective n Isolated Auxiliary/Housekeeping Power Supplies owners. Protected by U.S. Patents, including 5438499, 7463497, 7471522. TYPICAL APPLICATION 4V to 80V /5V Isolated Flyback Converter Efficiency vs Load Current IN OUT 100 + V V IN OUT 4V TO 80V 6:1 5V 220pF 90 100F 40H 1.1H 100 3 V IN 80 10F EN/UVLO SW V OUT LT8304 309k 70 GND R FB 20mA TO 2.4A (V = 24V) IN 20mA TO 3.6A (V = 48V) IN R INTV CC REF 60 20mA TO 4.2A (V = 72V) IN 1F 100k 10k V = 24V TC 50 IN 8304 TA01a V = 48V IN V = 72V IN 40 0 0.6 1.2 1.8 2.4 3.0 3.6 4.2 LOAD CURRENT (A) 8304 TA01b 8304fa 1 For more information www.linear.com/LT8304 EFFICIENCY (%)LT8304/LT8304-1 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) SW (Note 2) ............................................................150V TOP VIEW V ..........................................................................100V IN EN/UVLO 1 8 TC EN/UVLO ....................................................................V IN INTV 2 7 R CC REF 9 R ........................................................V 0.5V to V FB IN IN GND V 3 6 R IN FB Current Into R ....................................................200A FB GND SW 4 5 INTV , R , TC .........................................................4V CC REF S8E PACKAGE Operating Junction Temperature T Range (Notes 3, 4) J 8-LEAD PLASTIC SO LT8304E/LT8304E-1 .......................... 40C to 125C = 33C/W JA EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB LT8304I/LT8304I-1 ............................ 40C to 125C LT8304H/LT8304H-1 ......................... 40C to 150C Storage Temperature Range .................. 65C to 150C Lead Temperature (Soldering, 10 sec) ...................300C