SP6686 Datasheet, PDF (1/13 Pages) Sipex Corporation – 400mA Buck/Boost Charge Pump LED Driver

SP6686
400mA Buck/Boost Charge Pump LED Driver
FEATURES
■ Output Current up to 480mA
■ Up to 94% Efficiency in Torch Mode
■ Automatic Softstart limits inrush current
■ Adjustable FLASH mode
■ x1 and x2 Automatic Modes for High Efficiency
■ Minimum External Components: No Inductors
V_IN 1
C1 2
C2 3
FLASH 4
EN 5
10
SP6686 ⁹
8
10 Pin DFN
7
6
V_OUT
P_GND
S_GND
I_FB
I_SET
■ High Frequency Operation: 2.4 MHz
■ Low 50mV reference for low loss sensing
Now Available in Lead Free Packaging
■ 1µA shutdown current
■ PWM Dimming Control
■ Automatic switchover between buck/boost
■ Over voltage protection on output
■ Over current/temerature protection
■ Low Ripple and EMI
APPLICATIONS
■ White LED Torch/Flash for Cell
Phones, DSCs, and Camcorders
■ Generic Lighting/Flash/Strobe
Applications
■ Space Saving 10-pin 3mm x 3mm DFN
Package
■ White LED Backlighting
DESCRIPTION
The SP6686 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 SP6686 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 SP6686 is offered in 10-pin DFN package.
TYPICAL APPLICATION CIRCUIT
V_IN
(2.7 - 5.5V)
C_IN
2.2µF
C_FC
0.47µF
TORCH/FLASH
ENABLE
V_IN
® _VOUT
C1 _SP6686 P_GND
C2
FLASH
S_GND
FB
EN
R_SET
400mA FLASH
C_OUT
1µF
WLED
R_SET
106K Ω
R_SENSE
0.33Ω
Date: 03/10/06
SP6686 400mA, Buck/Boost Charge Pump LED Driver
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© Copyright 2006 Sipex Corporation