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Preliminary Product spec. T6311A
Low-Dropout, Constant-Current
White LED Bias Supply
FEATURES
• Low 200mV Dropout at 9mA
• Up to 150mA LED Bias Current
• 0.3% LED Current Matching
• Simple LED Brightness Control
• Low 40uA Supply Current
• Low 0.05uA Shutdown Current
• 2.5V to 5.5V Supply Voltage Range
• SOP-8 and SOT23-6 Package
• Output channel :
SOP-8 package for four channel
SOT23-6 package for three channel
GRNERAL DESCRIPTION
The T6311A low-dropout bias supply for
white LEDs is a high-performance alternative
to the simple ballast resistors used in
conventional white LED designs. The T6311A
uses a single resistor to set the bias current for
four LEDs, which are matched to 0.3%. The
T6311A consumes only 40uA of supply
current when enabled and 0.05uA when
disabled. The T6311A advantages over ballast
resistors include significantly better LED to
LED bias matching, much lower bias variation
with supply voltage variation, significantly
lower dropout voltage, and in some
applications, significantly improved efficiency.
The T6311A requires a 200mV dropout at a
9mA load on each output to match the LED
brightness. The T6311A is available in SOP-8
and SOT23-6 package.
Applications
• Cellular Phones
• Portable Communication Devices
• Handheld Electronics
• Digital Cameras
• PDAs
• LED/Display Back Light Driver
• LEDs for Camera Flash
PART NUMBER EXAMPLES
PART NO.
T6311A-D
T6311A-X
PACKAGE
SOP-8
SOT23-6
TM Technology Inc. reserves the right
P. 1
to change products or specifications without notice.
Publication Date: JUN. 2005
Revision: C
TMT [ TAIWAN MEMORY TECHNOLOGY ]
