Preliminary Datasheet LP3301 1.5MHz Step-up DC/DC Converter General Description The LP3301 is a 1.5MHz PWM boost switching regulator designed for constantcurrent white LED driver applications. The LP3301 implements a constant frequency 1.5MHz PWM control scheme. The high frequency PWM operation also saves board space by reducing external component sizes. To improve efficiency, the feedback voltage is set to 1.25V. Highly integration and internal compensation network minimizes as 5 external component counts. Optimized operation frequency can meet the requirement of small LC filters value and low operation current with high efficiency. Ordering Information LP3301 □ □ Features High Efficiency: 85% 1.5MHz Fixed-Frequency PWM Operation 36V 500mA Integrated switch Shutdown Supply Current:<1uA Available in SOT23-5 Package Built-in Over Voltage Protection of 29V Minimize the External Component RoHS Compliant and 100% Lead (Pb)-Free Applications LCD Bias Supply PDA DSC Typical Application Circuit □ F:Pb-Free Package Type B5: SOT-23-5 Pin Configurations Marking information Please view website. LP3301-datasheet Dec.-2005 1 -1 Preliminary Datasheet LP3301 Functional Pin Description SOT-23-5 Pin Name Pin Function Switch Pin. Connect this Pin to inductor and catch diode. Minimize the track 1 LX 2 GND area to reduce EMI. Ground Pin Feedback Reference Voltage Pin. Series connect a resistor between WLED 3 FB and ground as a current sense. Sense the current feedback voltage to set the current rating. Chip Enable (Active High). Voltage sensing input to trigger the function of 4 SHDN over voltage protection. Note that this pin is high impedance. There should be a pull low 100kΩ resistor connected to GND when the control signal is floating. 5 VIN Supply Input Voltage Pin. Bypass 1uF capacitor to GND to reduce the input noise. Function Block Diagram LP3301-datasheet Dec.-2005 2 -2 LP3301 Preliminary Datasheet Absolute Maximum Ratings Supply Input Voltage--------------------------------------------------------------------------------------------------−0.3V to 16V LX Input Voltage -------------------------------------------------------------------------------------------------------−0.3V to 36V SHDN Input Voltage ---------------------------------------------------------------------------------------------−0.3V to 16V OVP Voltage------------------------------------------------------------------------------------------------------------−0.3V to 29V The Other Pins ---------------------------------------------------------------------------------------------------------−0.3V to 5V Power Dissipation, PD @ TA = 25°C SOT-23-5 -----------------------------------------------------------------------------------------------------------------------0.455W Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------------- 260°C Operation Temperature Range --------------------------------------------------------------------------------------−40°C to 80°C Junction Temperature Range ----------------------------------------------------------------------------------------0°C to 125°C Storage Temperature Range ----------------------------------------------------------------------------------------−65°C to 150°C Operation Junction Temperature Range --------------------------------------------------------------------------0°C to 125°C Electrical Characteristics Parameter Symbol Test Condition Min Typ Max Units 16 V System Supply Input Operation voltage Range VDD 2.6 Under Voltage Lock Out VDD -- Supply Current IDD Shut Down Current IDD Line Regulation FB=0V, Switch 2.2 V 2 3.5 mA VEN < 0.4V 0.1 1 uA VIN : 3.0~4.3V 3 % Oscillator Operation Frequency 1.1 1.5 Maximum Duty Cycle 85 90 Dimming Frequency 100 FOSC 1.9 MHz % 100k Hz 1330 mV Reference Voltage Feedback Voltage (Note 4) LP3301 1170 1250 RDS(ON) -- 0.6 MOSFET On Resistance of MOSFET Ω Protection OVP Threshold VOVP OVP Sink Current Switching Current Limit Shut Down Voltage VEN -- Enable Voltage VEN 1.5 Soft Star time LP3301-datasheet 29 V 5 μA 500 mA 0.4 V 550 Dec.-2005 3 -3 V uS Preliminary Datasheet Packing information LP3301-datasheet Dec.-2005 4 -4 LP3301