NCP5006

NCP5006 Compact Backlight LED Boost Driver The NCP5006 is a high efficiency boost converter operating in current loop, based on a PFM mode, to drive White LED. The current mode regulation allows a uniform brightness of the LEDs. The chip has been optimized for small ceramic capacitors, capable to supply up to 1.0 W output power. Features http://onsemi.com MARKING DIAGRAM 5 5 1 TSOP−5 SN SUFFIX CASE 483 DCSYW 1 • 2.7 to 5.5 V Input Voltage Range • Vout to 24 V Output Compliance Allows up to 5 LEDs Drive in • • • • • • • • • • • Series Built−in Overvoltage Protection Inductor Based Converter brings up to 90% Efficiency Constant Output Current Regulation 0.3 mA Standby Quiescent Current Includes Dimming Function (PWM) Enable Function Driven Directly from Low Battery Voltage Source Automatic LEDs Current Matching Thermal Shutdown Protection All Pins are Fully ESD Protected Low EMI Radiation Pb−Free Package is Available DCS = Device Code Y = Year W = Work Week PIN CONNECTIONS Vout GND FB 1 2 3 (Top View) 4 EN 5 Vbat Typical Applications • LED Display Back Light Control • Keyboard Back Light • High Efficiency Step Up Converter ORDERING INFORMATION Device NCP5006SNT1 NCP5006SNT1G Package TSOP−5 TSOP−5 (Pb−Free) Shipping† 3000 Tape & Reel 3000 Tape & Reel †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D. © Semiconductor Components Industries, LLC, 2004 1 July, 2004 − Rev. 0 Publication Order Number: NCP5006/D NCP5006 Vbat U1 4 5 C1 4.7 mF L1 22 mH GND 2 3 GND Vout FB NCP5006 MBR0530 C2 1.0 mF 1 D1 GND Vbat EN Vbat R1 GND 15 W D6 D5 D4 D3 D2 GND LWT67C LWT67C LWT67C LWT67C LWT67C Figure 1. Typical Application Thermal Shutdown Current Sense Vbat 5 Vbat Vsense CONTROLLER EN 4 100 k 1 Vout Q1 GND FB 3 300 k +200 mV Band Gap − + GND 2 GND Figure 2. Block Diagram http://onsemi.com 2 NCP5006 PIN FUNCTION DESCRIPTION Pin 1 Pin Name Vout Type POWER Description This pin is the power side of the external inductor and must be connected to the external Schottky diode. It provides the output current to the load. Since the boost converter operates in a current loop mode, the output voltage can range up to +24 V but shall not extend this limit. However, if the voltage on this pin is higher than the Over Voltage Protection threshold (OVP) the device comes back to shutdown mode. To restart the chip, one must either send a Low to High sequence on Pin EN, or switch off the Vbat supply. A capacitor must be used on the output voltage to avoid false triggering of the OVP circuit. This capacitor should be 1.0 mF minimum. Ceramic type, (ESR