RT9285A Datasheet, PDF (1/12 Pages) Richtek Technology Corporation – Tiny Package, High Performance, Diode Embedded White LED Driver

Preliminary
RT9285A/B
Tiny Package, High Performance, Diode Embedded White
LED Driver
General Description
Features
The RT9285 is a high frequency asynchronous boost
converter with internal diode, which can support 2 to 5
White LEDs for backlighting and OLED power supply. The
Internal soft start function can reduce the inrush current.
The device operates with 1MHz fixed switching frequency
to allow small external components and to simplify possible
EMI problems. The device comes with 20V over voltage
protection to allow inexpensive and small-output capacitors
with lower voltage rating. The LED current is initially set
with the external sense resistor R_SET, and the feedback
voltage is 250 mV. Tiny package type TSOT-23-6 and
WDFN-8L 2x2 packages provide the best solution for PCB
space saving and total BOM cost.
Ordering Information
RT9285
Package Type
QW : WDFN-8L 2x2 (W-Type)
J6 : TSOT-23-6
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Dimming
A : Digital Pulse Dimming
B : PWM Clock Dimming
Note :
Richtek Pb-free and Green 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.
}100%matte tin (Sn) plating.
l V_IN Operating Range : 2.7V to 5.5V
l Up to 85% Efficiency
l 22V Internal Power N-MOSFET
l 1MHz Switching Frequency
l Built-in Diode
l Digital Dimming with Zero-Inrush
l Input UVLO Protection
l Output Over Voltage Protection
l Internal Soft Start and Compensation
l TSOT-23-6 and 8-Lead WDFN Package
l RoHS Compliant and 100% Lead (Pb)-Free
Applications
l Cellular Phones
l Digital Cameras
l PDAs and Smart Phones
l Porbable Instruments
l MP3 Player
l OLED Power
Pin Configurations
(TOP VIEW)
AGND 1
LX 2
NC 3
PGND 4
8 FB
7 EN
6 VOUT
9 _{5 VDD}
WDFN-8L 2x2
VDD VOUT EN
6
5
4
1
2
3
LX GND FB
TSOT-23-6
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area, otherwise visit our website for detail.
Note : There is no pin1 indicator on top mark for TSOT-23-6
type, and pin 1 will be lower left pin when reading top mark
from left to right.
DS9285A/B-02 August 2007
www.richtek.com
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