AP8803WTG-7 Diodes Incorporated

AP8803 30V 1A BUCK LED DRIVER Description Pin Assignments The AP8803 is a step-down DC/DC converter designed to drive LEDs with a constant current. The device can drive up to 7 LEDs, depending on the forward voltage of the LEDs, in series from a voltage source of 8V to 30V. Series connection of the LEDs provides SW 1 V 5 IN identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The AP8803 switches at frequency up GND 2 to 700kHz. This allows the use of small size external components, hence minimizing the PCB area needed. CTRL 4 SET 3 Maximum output current of AP8803 is set via an external resistor connected between the V and SET input pins. Dimming is achieved IN Top View by applying either a DC voltage or a PWM signal at the CTRL input pin. An input voltage of 0.2V or lower at CTRL shuts down the output at SW and puts the device into a low-current standby state. Features LED Driving Current up to 1A High Efficiency Up to 92% Operating Input Voltage Up to 30V High Switching Frequency Up to 700kHz PWM/DC Input for Dimming Control Built-In Output Open-Circuit Protection TSOT25: Available in Green Molding Compound (No Br, Sb) with lead Free Finish/ RoHS Compliant Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See AP8803 Pin Descriptions Pin Name Function SW Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin to reduce EMI. GND GND pin SET Set Nominal Output Current Pin. Configure the output current of the device. Dimming and On/Off Control Input. Leave floating for normal operation. (V = V = 1.25V giving nominal average output current I = 0.1/R ) CTRL REF OUTnom S CTRL Drive to voltage below 0.2V to turn off output current Drive with DC voltage (0.3V < V < 1.25V) to adjust output current from 25% to 100% of I CTRL OUTnom Input voltage of 0.2V or lower forces the device into low current standby mode and shuts off the output. A PWM signal allows the output current to be adjusted above or below the level set by the resistor connected to SET input pin. V Input Supply Pin. Must be locally decoupled to GND with > 2.2F X7R ceramic capacitor. IN Functional Block Diagram Absolute Maximum Ratings ( T = +25C, unless otherwise specified.) A Symbol Parameter Rating Unit Continuous V pin voltage -0.3 to +30 IN V V IN Transient (t < 0.5s) 40 SW voltage -0.3 to +30 V V SW Transient (t < 0.5s) 40 V CTRL pin input voltage -0.3 to +6 V CTRL I Switch current 1.25 A SW ESD Human Body Model ESD 500 V HBM ESD Machine Model ESD <100 V MM T Junction Temperature 150 C J T Lead Temperature Soldering 300 C LEAD T Storage Temperature Range -65 to +150 C ST Caution: Stresses greater than the Absolute Maximum Ratings specified above, may cause permanent damage to the device. These are stress ratings only functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when handling and transporting these devices 2 of 10 August 2012 AP8803 Diodes Incorporated www.diodes.com Document number: DS31970 Rev. 5 - 2