RT9300A_11 Datasheet, PDF (1/9 Pages) Richtek Technology Corporation – Tiny Package, Low Dropout Current Source

RT9300A/B
Tiny Package, Low Dropout Current Source
General Description
The RT9300A/B low-dropout bias supply for white LEDs
is a high-performance alternative to the simple ballast
resistors used in conventional white LED designs. The
RT9300A/B uses an internal resistor to set the bias
current for four LEDs, which are matched to 5%. The
RT9300A/B's advantages over ballast resistors include
much lower bias variation with supply voltage variation,
significantly lower dropout voltage, and in some applications,
significantly improved efficiency. The RT9300A/B requires
only a 60/45mV dropout voltage at a 20/15mA load on
each output to match the LED brightness.
Ordering Information
RT9300A/B
Package Type
E : SOT-23-6
Lead Plating System
P : Pb Free
G : Green (Halogen Free and Pb Free)
Note :
Sink Current
A : 20mA
B : 15mA
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Features
z Low 60/45mV Dropout at 20/15mA
z 5% LED Current Matching
z Simple LED Brightness Control
z 2.5V to 5.5V Supply Voltage Range
z Thermal Shutdown Protection
z RoHS Compliant and 100% Lead (Pb)-Free
Applications
z Next-Generation Wireless Handsets
z PDAs, Palmtops, and Handy Terminals
z Digital Cameras, Camcorders
z Battery-Powered Equipment
Pin Configurations
(TOP VIEW)
LED1 LED2 LED3
6
5
4
2
3
EN GND LED4
SOT-23-6
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Typical Application Circuit
V_IN
Enable
6
5
4
3
LED1 LED2 LED3 LED4
1 _EN
RT9300A/B
GND
2
C
0.1uF
Figure 1. Application Circuit for Backlight.
DS9300A/B-05 April 2011
www.richtek.com
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