LTC3539/LTC3539-2 ELECTRICALCHARACTERISTICS The l denotes the specifications which apply over the specifiedtemperature range of –40°C to 85°C, otherwise specifications are at TA = 25°C. VIN = 1.2V, VOUT = 3.3V, unless otherwise noted. PARAMETERCONDITIONSMINTYPMAXUNITS Maximum Duty Cycle VFB = 1.15V l 87 90 % Minimum Duty Cycle VFB = 1.3V l 0 % Switching Frequency LTC3539 l 0.7 1 1.3 MHz LTC3539-2 l 1.8 2 2.4 MHz MODE Input High Voltage 0.88 V MODE Input Low Voltage 0.3 V MODE Input Current VMODE = 1.2V 0.3 1 µA SHDN Input High Voltage 0.88 V SHDN Input Low Voltage 0.3 V SHDN Input Current VSHDN = 1.2V 0.3 1 µA VSHDN = 3.3V 1 2 µA Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 4: Current measurements are made when the output is not switching. may cause permanent damage to the device. Exposure to any Absolute Note 5: This IC includes overtemperature protection that is intended Maximum Rating condition for extended periods may affect device to protect the device during momentary overload conditions. Junction reliability and lifetime. temperature will exceed 125°C when overtemperature protection is active. Note 2: The LTC3539E/LTC3539E-2 is guaranteed to meet performance Continuous operation above the specified maximum operating junction specifications from 0°C to 85°C. Specifications over –40°C to 85°C temperature may result in device degradation or failure. operating temperature range are assured by design, characterization and Note 6: Failure to solder the exposed backside of the package to the PC correlation with statistical process controls. board ground plane will result in a thermal resistance much higher than Note 3: Specification is guaranteed by design and not 100% tested in 64°C/W. production. TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)Efficiency vs Load Current andEfficiency vs Load Current andVIN, VOUT = 1.8VVIN, VOUT = 3.3V 100 1000 100 1000 90 90 80 100 80 EFFICIENCY POWER LOSS (mW) 100 POWER LOSS (mW) 70 70 EFFICIENCY 60 10 60 50 50 10 POWER LOSS 40 1 40 EFFICIENCY (%) EFFICIENCY (%) POWER LOSS 30 30 1 20 0.1 20 VIN = 1V VIN = 1.2V 10 VIN = 1.2V 10 VIN = 1.8V VIN = 1.5V VIN = 3V 0 0.01 0 0.1 0.1 1 10 100 1000 0.1 1 10 100 1000 LOAD CURRENT (mA) LOAD CURRENT (mA) 3539 G01 3539 G02 35392fc For more information www.linear.com/3539/3539-2 3 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Related Parts