LTC3207/LTC3207-1
600mA Universal
Multi-Output LED/CAM Driver
FEATURES
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DESCRIPTION
The LTC
®
3207/LTC3207-1 are highly integrated multi-display
LED drivers. The device contains a high-efficiency, low-noise
charge pump to provide power to 12 universal LED current
sources and one camera LED current source. The LTC3207/
LTC3207-1 require only five small ceramic capacitors to
form a complete LED power supply and current controller.
In addition there are two I
2
C addresses available.
The display currents are set by an internal precision cur-
rent reference. Independent dimming, On/Off, blinking
and gradation control for all universal current sources is
achieved via the I
2
C serial interface. 6-bit linear DACs are
available for adjusting brightness levels for each universal
LED current source. The CAM current source has a 4-bit
linear DAC to adjust brightness.
The LTC3207/LTC3207-1 charge pumps optimize efficiency
based on the voltage across the LED current sources. The
device powers-up in 1x mode and will automatically switch
to boost mode whenever any enabled LED current source
begins to enter dropout. The first dropout switches the
IC into 1.5x mode and a subsequent dropout switches
the LTC3207/LTC3207-1 into 2x mode. The device resets
to 1x mode whenever a data register is updated via the
I
2
C port.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners. Protected by U.S. Patents,
including 6411531.
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Low Noise, Multi-Mode Charge Pump (1x, 1.5x, 2x)
Provides Up to 91% Efficiency
Slew Limited Switching Reduces Conducted and
Radiated Noise (EMI)
Up to 600mA Total Output Current
Twelve 28mA Universal Current Sources with
64-Step Linear Brightness Control
425mA CAM LED Current Source with 16-Step
Linear Brightness Control and 2-Second High
Current Safety Timer
Independent On/Off, Brightness Level, Blinking and
Gradation Control for Each Current Source Using
2-Wire I
2
C
TM
Interface
Internal Current Reference
Two I
2
C Addresses are Available
(LTC3207 00110110, LTC3207-1 00110100)
Configurable ENU Pin for Asynchronous LED
On/Off Control
Automatic or Forced Mode Switching
Internal Soft-Start Limits Inrush Current
Short-Circuit/Thermal Protection
4mm × 4mm 24-Pin QFN Plastic Package
APPLICATIONS
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Video Phones with QVGA
+
Displays
TYPICAL APPLICATION
4-LED MAIN, 2-LED SUB, Dual RGB and Camera Light
C2
2.2µF
C3
2.2µF
V
BAT
C1
2.2µF
C1P C1M C2P C2M
V
BAT
CPO
LTC3207/LTC3207-1
DV
CC
C4
4.7µF
MAIN
SUB
RGB
RGB
CAM
DV
CC
0.1µF
ULED1-12
I
2
C
ENABLE DISABLE
LOW HI
2
SCL/SDA
ENU
CAMHL
GND
CAM
12
3207 TA01
3207fc
1
LINER [ LINEAR TECHNOLOGY ]
