POWER LOSS (mW) LT8570/LT8570-1 Boost/SEPIC/Inverting DC/DC Converter with 65V Switch, Soft-Start and Synchronization FEATURES DESCRIPTION n 65V Power Switch The LT 8570 and LT8570-1 are PWM DC/DC converters. n Current Limit Options of 0.5A (LT8570) or 0.25A The LT8570 contains a 0.5A, 65V power switch, while (LT8570-1) the LT8570-1 contains a 0.25A, 65V power switch. The n Adjustable Switching Frequency LT8570 and LT8570-1 can be configured as either a boost, n Single Feedback Resistor Sets V SEPIC or inverting converter. OUT n Synchronizable to External Clock The LT8570/LT8570-1 have an adjustable oscillator, set n High Gain SHDN Pin Accepts Slowly Varying by a resistor from the RT pin to ground. Additionally, the Input Signals LT8570/LT8570-1 can be synchronized to an external n Wide Input Voltage Range: 2.55V to 40V clock. The switching frequency of the part may be free n Low V Switch CESAT running or synchronized, and can be set between 200kHz n Integrated Soft-Start Function and 1.5MHz. n Easily Configurable as a Boost, SEPIC, or Inverting The LT8570/LT8570-1 also feature innovative SHDN pin Converter n circuitry that allows for slowly varying input signals and User Configurable Undervoltage Lockout (UVLO) n an adjustable undervoltage lockout function. Pin Compatible with LT3580 and LT8580 n Tiny Thermally Enhanced 8-Lead 3mm 3mm DFN Additional features such as frequency foldback and soft- and 8-Lead MSOP Packages start are integrated. The LT8570/LT8570-1 are available in tiny thermally enhanced 3mm 3mm 8-lead DFN and APPLICATIONS 8-lead MSOP packages. n VFD Bias Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n TFT-LCD Bias Supplies ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7579816. n GPS Receivers n DSL Modems n Local Power Supply TYPICAL APPLICATION Efficiency and Power Loss 1.5MHz, 5V to 12V Boost Converter 100 320 22H V OUT V IN 90 280 12V 5V 125mA 80 240 10k 70 200 V SW IN 130k 60 160 SHDN FBX 2.2F LT8570 1F 50 120 SYNC VC 40 80 6.19k RT GND SS 47pF EFFICIENCY 30 40 POWER LOSS 56.2k 0.1F 2.2nF 20 0 8570 TA01a 0 25 50 75 100 125 LOAD CURRENT (mA) 8570 TA01b 85701fa 1 For more information www.linear.com/LT8570 EFFICIENCY (%)LT8570/LT8570-1 ABSOLUTE MAXIMUM RATINGS (Note 1) V Voltage .................................................0.3V to 40V SYNC Voltage ............................................ 0.3V to 5.5V IN SW Voltage ................................................0.4V to 65V Operating Junction Temperature Range RT Voltage ...................................................0.3V to 5V LT8570E, LT8570-1E (Notes 2, 5) ......40C to 125C SS Voltage ................................................ 0.3V to 2.5V LT8570I, LT8570-1I (Notes 2, 5) ........40C to 125C FBX Voltage .................................................................5V LT8570H, LT8570-1H (Notes 2, 5) .....40C to 150C FBX Current ............................................................1mA Storage Temperature Range ..............65C to 150C VC Voltage ................................................... 0.3V to 2V Lead Temperature (Soldering, 10 sec) SHDN Voltage ............................................0.3V to 40V MS8E Package Only ..........................................300C PIN CONFIGURATION TOP VIEW TOP VIEW FBX 1 8 SYNC FBX 1 8 SYNC VC 2 7 SS VC 2 9 7 SS 9 GND 6 GND V 3 RT V RT IN 3 6 IN SW 4 5 SHDN SW 4 5 SHDN MS8E PACKAGE 8-LEAD PLASTIC MSOP DD PACKAGE = 35C/W TO 40C/W JA 8-LEAD (3mm 3mm) PLASTIC DFN EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB = 43C/W JA EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB