Rev 0.1 DIO5151B 700mA/1A Buck/Boost Charge Pump LED Driver Features Descriptions Output Current : The DIO5151B is a current-regulated charge DIO5151BED8: 700mA pump ideal for powering high brightness LEDs DIO5151BCD10: 1A for camera flash applications. The charge pump Up to 90% Efficiency in Torch Mode can be set to regulate two current levels for Adjustable FLASH Mode Current FLASH and TORCH modes. 1 and 2 Automatic Modes for High Efficiency Input Voltage Range: 3V to 5.5V The DIO5151B automatically switches modes Minimum External Components: No Inductors between step-up and step-down ensuring that High Frequency Operation: 2MHz LED current does not depend on the forward Low 47mV Reference for Low Loss Sensing voltage. It switches at 2MHz, allowing the use of IQ < 1A in Shutdown tiny components. The supply voltage ranges Built-In Soft Start Limits Inrush Current from 3V to 5.5V and is ideally suited for all Low Input and Output Ripple and Low EMI applications powered by a single LI-Ion battery Output Over Voltage Protection cell or three to four NiCd, NiMH, or Alkaline Output Open and Output Short Protection battery cells. Over-current and Over-temperature Protection The DIO5151B also features a very low shutdown Package: DFN2*2.2-8, DFN3*3-10 current, an automatic soft-start mode to limit Applications inrush current, as well as over current, over Cellular Telephones voltage and over thermal shutdown control. A Digital Still Cameras low current sense reference voltage (47mV) Mobile Internet Device allows the use of small 0603 current sensing USB Bus-Powered Chargers resistors. Block Diagram The DIO5151B is available in Green DFN2*2.2-8, DFN3*3-10 package and is specified over an VIN VOUT VIN 3-5.5V 4.7F 1F ambient temperature range of -40C to +85C. White LED C1 1F C2 TORCH/FLASH DIO5151B FLASH ENABLE EN FB 0.22 RSET GND 86.6K Ordering Information Order Part Number Top Marking T Package A DIO5151BED8 51B Green -40 to +85C DFN2*2.2-8 Tape & Reel, 3000 DIO5151BCD10 D51B Green -40 to +85C DFN3*3-10 Tape & Reel, 5000 www.dioo.com 2015 DIOO MICROCIRCUITS CO., LTD DIO5151B Rev. 0.1 700mA/1A Buck/Boost Charge Pump LED Driver DIO5151B Pin Assignment DFN2*2.2-8 DFN3*3-10 Figure 1 Pin Assignment (Top View) Pin Descriptions Name Description Connect a resistor from this pin to ground. When in FLASH mode (FLASH = High) this resistor sets the RSET current regulation point according to the following: V = (1.26V/ R ) 10.2K. FB SET FB Feedback input for the current control loop. Connect directly to the current sense resistor. Logic input to toggle operation between FLASH and TORCH mode. In TORCH mode FB is regulated to the internal 47mV reference. In FLASH mode FB reference voltage can be adjusted by changing the FLASH resistor from R pin to ground. Choose the external current sense resistor (R ) based on desired SET SENSE current in TORCH mode and Flash mode. Charge Pump Output Voltage. Decouple with an external capacitor. At least 1F is recommended. VOUT If Higher value capacitor is used, output ripple is smaller. Input voltage for the charge pump. VIN Decouple with 4.7F or 10F ceramic capacitor close to the pins of the IC. Positive input for the external flying capacitor. C1 Connect a ceramic 1F capacitor close to the pins of the IC. Negative input for the external flying capacitor. C2 Connect a ceramic 1F capacitor close to the pins of the IC. EN Shutdown control input. Connect to VIN for normal operation, connect to ground for shutdown. SGND Internal ground pin. Control circuitry returns current to this pin. PGND Power ground pin. Flying capacitor current returns through this pin. GND Exposed pad should be soldered to PCB board and connected to GND. www.dioo.com 2015 DIOO MICROCIRCUITS CO., LTD DIO5151B Rev. 0.1