RT8489 Datasheet, PDF (3/16 Pages) Richtek Technology Corporation – High Voltage 4-CH LED Driver Controller

RT8489
Pin No.
Pin Name
13, 16, 19, 22 SENSEx
14, 17, 20, 23 GATEx
15, 18, 21, 24 LEDx
Pin Function
Source of External MOSFETx (x = 1 to 4).
The SENSEx pins are regulated around 225mV. Connect a sense resistor from
this pin to GND. The LED current is set by I_LED = 225mV / (sense resistance)
when V_ACTL is greater than 1.4V.
Gate Drive Output for External MOSFETx (x = 1 to 4).
LED String Voltage Sense Input. Connect these pins to the Drain of External
MOSFETx (x = 1 to 4). Short the pin to GND if not used.
Function Block Diagram
VCC
RSET
OVP
5.5V +
-
1.23V -
+
OSC
10V
+
-
PWM
Control
VC
SS
EN
DCTL
ACTL
3.2V
8µA
1.4V +
-
1.4V
+
-
LED1
LED2
VOUT
Regulation
Unit
LED3
LED4
Shutdown
3.2V
1.4V
+
-
3.2V
+
-
GBIAS
3.2V
+
-
GBIAS
3.2V
+
-
GBIAS
3.2V
+
-
GBIAS
GBIAS
GATE
ISENSE
LED1
GATE1
SENSE1
LED2
GATE2
SENSE2
LED3
GATE3
SENSE3
LED4
GATE4
SENSE4
GND
Copyright ©2012 Richtek Technology Corporation. All rights reserved.
DS8489-00 November 2012
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
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