SP6685_06 Datasheet, PDF (1/16 Pages) Sipex Corporation – 700mA Buck/Boost Charge Pump LED Driver

SP6685
700mA Buck/Boost Charge Pump LED Driver
FEATURES
■ Output Current up to 700mA
VIN 1
10 VOUT
■ Up to 94% Efficiency in Torch Mode
■ Adjustable FLASH Mode Current
■ Minimum External Components: No Inductors
■ Automatic Buck/Boost Mode Switchover
C1 2
C2 3
FLASH 4
SP6685 ⁹
10 Pin DFN ⁸
7
PGND
SGND
FB
■ Wide V_IN Range: 2.7V to 5.5V
EN 5
6 _RSET
■ High Frequency Operation: 2.4 MHz
■ Low 50mV Reference for low Loss Sensing ^{Now Available in Lead Free Packaging}
■ I_Q < 1μA in Shutdown
■ PWM Dimming Control
■ Automatic Soft Start Limits Inrush Current
■ Overvoltage Protection on Output
APPLICATIONS
■ White LED Torch/Flash for Cell
Phones, DSCs, and Camcorders
■ White LED Backlighting
■ Overcurrent/Temperature Protection
■ Low Ripple and EMI
■ Generic Lighting/Flash/Strobe
Applications
■ Ultra-low Dropout Voltage in Buck Mode
■ General Purpose High Current Boost
■ Space Saving 10-pin 3mm x 3mm DFN Package
DESCRIPTION
The SP6685 is a current-regulated charge pump ideal for powering high brightness LEDs for
camera flash applications. The charge pump can be set to regulate two current levels for
FLASH and TORCH modes. The SP6685 automatically switches modes between step-up
and step-down ensuring that LED current does not depend on the forward voltage. A low
current sense reference voltage (50mV) allows the use of small 0603 current sensing
resistors. The SP6685 is offered in the 10-pin DFN package.
V_IN
(2.7 - 5.5V)
O
C_IN
4.7μF
C_FC
1μF
TORCH/FLASH
ENABLE
TYPICAL APPLICATION CIRCUIT
V_IN
® _VOUT
C1 _SP6685 P_GND
C2
FLASH
EN
S_GND
FB
R_SET
C_OUT
1μF
R_SET
88KΩ
WLED
R_SENSE
0.22Ω
Date: 7/6/06 Rev B
SP6685, 700mA Buck/BoostCharge Pump LED Driver
1
© 2006 Sipex Corporation