POWER MANAGEMENT
Description
The SC615 is a high-current charge pump designed spe-
cifically for use with white LEDs used in camera flash
applications. Only two small bucket capacitors are re-
quired to develop the output drive, providing a low EMI
solution compared to inductive boost regulators.
The SC615 has two modes of operation: Flash mode
and Spotlight mode. The SC615 is capable of delivering
500mA of peak current for a duration of 500ms in Flash
mode. In Spotlight mode the SC615 outputs 100mA
and can remain enabled continuously.
A minimum 0.5Ω sense resistor is used to set the cur-
rent through the LED in both modes. This resistor dissi-
pates up to 0.125W, reducing the power dissipation re-
quirement of the SC615. The flash input (FLASH) over-
rides the control input (CTRL) to make sure the flash func-
tion is activated when called for.
The thermally efficient MLPD-10 package and ceramic
bypass and bucket capacitors help make the SC615 a
high output current driver that requires a minimal amount
of PCB area.
Charge Pump
Flash LED Driver
Features
500mA Output Current - Flash Mode
3.0V to 5.25V Input Range
Two Selectable Modes - Flash and Spotlight
External Flash Control Pin for Synchronization to a
Camera Module or Graphics Controller
Spotlight Mode Current Setting - 100mA
Short Circuit, Over-Voltage, and Over-Temperature
Protection
Soft-Start Functionality
Two Control Inputs for Maximum Versatility
Shutdown Current < 2µA
Micro Lead-frame Package MLPD-10, 3mm x 3mm
SC615
Applications
Mobile Camera Phones
Digital Cameras
PDAs with Built-in Cameras
Multi-LED Backlit LCDs
Application Circuit
1
SC615
VIN
C1+
C1-
C2+
C2-
VOUT
GND
ISET
CTRL
FLASH
9
3.0V to 5.25V
10µF
1µF
white LED
3
6
7
5
8
4
10
1µF
1µF
2
0.5Ω
FLASH
CTRL
July 11, 2005
1
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SEMTECH [ SEMTECH CORPORATION ]
