SC615A_08 Datasheet, PDF (1/12 Pages) Semtech Corporation – Charge Pump Flash LED Driver

SC615A
POWER MANAGEMENT
Charge Pump Flash
LED Driver
Description
Features
The SC615A is a high-current charge pump designed
specifically for use with white LEDs used in camera
flash applications. Only two small bucket capacitors are
required to develop the output drive, providing a low EMI
solution compared to inductive boost regulators.
The SC615A has two modes of operation: Flash mode and
Spotlight mode. In Flash mode, the SC615A is capable
of delivering 500mA of regulated current for a duration
of 500ms or up to 700mA for a reduced duration. In
Spotlight mode the SC615A outputs 40% of the Flash
mode current and can remain enabled continuously.
An external resistor is connected in series with the LED to
set the current. In Flash mode, this resistor can dissipate
up to 175mW, reducing the power dissipation requirement
of the SC615A. The flash input (FLASH) overrides the
control input (CTRL) to make sure the flash function is
activated when called for.
The thermally efficient MLPD-10 package and ceramic
bypass and bucket capacitors make the SC615A a high
output current driver that requires minimal PCB area.
‹ Two Selectable Modes - Flash and Spotlight
‹ Up to 700mA Output - Flash Mode
‹ Up to 280mA Output - Spotlight Mode
‹ 500mA Over Temperature Range and Voltage Range
- Flash Mode
‹ Spotlight mode set to 40% of Flash Current
‹ 3.0V to 5.25V Input Range
‹ External Flash Control Pin for Synchronization to a
Camera Module or Graphics Controller
‹ Short Circuit, Over-Voltage, and Over-Temperature
Protection
‹ Soft-Start Functionality
‹ Two Control Inputs for Maximum Versatility
‹ Shutdown Current < 2μA
‹ Micro Lead Package MLPD-10, 3mm x 3mm
Applications
‹ Mobile Camera Phones
‹ Digital Cameras
‹ PDAs with Built-in Cameras
Typical Application Circuit
3.0V to
5.25V
10μF
1μF
1μF
FLASH
CTRL
1
SC615A
9
VIN
VOUT
8
C1+
3
1μF
GND
4
C1-
6
ISET
10
C2+
7
CTRL
2
C2-
5
FLASH
white LED
0.5Ω
March 5, 2008
www.semtech.com
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