NCP5030

NCP5030 Buck-Boost Converter to Drive a Single LED from 1 Li-Ion or 3 Alkaline Batteries The NCP5030 is a fixed frequency PWM buck−boost converter optimized for constant current applications such as driving high−powered white LED. The buck−boost is implemented in an H−bridge topology and has an adaptive architecture where it operates in one of three modes: boost, buck−boost, or buck depending on the input and output voltage condition. This device has been designed with high−efficiency for use in portable applications and is capable of driving in DC up to 900 mA into a high power LED for flashlight / torch applications. To protect the device cycle−by−cycle current limiting and a thermal shutdown circuit have been incorporated as well as output over−voltage protection. The 700 kHz switching frequency allows the use of a low value 4.7 mH and ceramic capacitors. The NCP5030 is housed in a low profile space efficient 3x4 mm thermally enhanced WDFN. Features Efficiency: 87% at 500 mA and 3.3 V VIN Internal Synchronous Rectifier, No Schottky Diodes Adjustable Switching Limit Current to Optimize inductor size 0.3 mA Shut−down Control with “True−Cut off” Input Voltage Range from 2.7 V to 5.5 V 200 mV Feedback Voltage Output Over−voltage and Thermal Shut Down Protection Typical Applications Portable Flashlight / Torch Lights Vin 1 Cell Li−Ion 2.7 to 5.5 Cin 1 mF C2 10 mF Cin 39 k R1 ENABLE PCA CTRL VIN PVIN LX1 LX1 LX2 4.7 mH L1 VOUT VS NCP5030 C3 22 mF D1 Co...