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OB3350
Cost Effective LED Controller
GENERAL DESCRIPTION
OB3350 is a highly integrated and cost effective Light Emitting Diode (LED) driver optimized for LCD monitor and LCD TV backlighting application. It provides a high performance LED backlight solution with minimized BOM count. The OB3350 contains a PWM boost driver which uses current mode control and fixed frequency operation to regulate the LED current. The LED current is sensed through an external current sense resistor. The voltage across the sensing resistor is compared with reference level of 300mV, the error is amplified to control the pulse width of the power switch thus to regulate the current flowing the LED. The OB3350 offers external low frequency PWM (LPWM) dimming method for a wide range of dimming control. The OB3350 offers comprehensive protection such as power MOSFET over current protection (OCP), output over voltage protection (OVP), IC power supply under voltage lockout (UVLO), and LED open protection.
FEATURES
Current Mode PWM Controller With Good Dynamic Response 8V to 35V Input Voltage Range External PWM Dimming Mode Over Voltage Protection Over Current Protection Under Voltage Lockout (UVLO) Thermal Shutdown
APPLICATIONS
LCD Monitor LCD TV Flat panel display
The OB3350 is offered in SOP-8 Packages.
TYPICAL APPLICATION
Figure1. OB3350 Typical Application Schematic
©On-Bright Electronics
Confidential -1-
Preliminary datasheet OB_DOC_DS_335000
OB3350
Cost Effective LED Controller
Absolute Maximum Ratings
Parameter
VIN Input Voltage to GND
I/O to GND Operating Ambient Temp. TA Operating Junction Temp. TJ Min/Max Storage Temp. Tstg Lead Temp. (10 Sec)
Value
-0.3V to 40V -0.3V to 7V -40 ~ 85 -40 ~ 150 -55 ~150 260
Note: Stresses beyond those listed under absolute maximum
ratings may cause permanent damage to the device. These
are stress ratings only, functional operation of the device at
these or any other conditions beyond those indicated under
recommended operating conditions is not implied. Exposure
to absolute maximum-rated conditions for extended periods
may affect device reliability.
Recommended Operating Range
Parameter Vin Voltage Burst Dimming Frequency
Value 8V to 35V 100Hz to 1KHz
Package Thermal Characteristics
Parameter Thermal Resistance JA (SOP)
Value 150 /W
Ordering Information
Part Number
Description
OB3350CP
SOP8, pb-free in tube
OB3350CPA
SOP8, pb-free in T&R
OB3350 X
X
X
Cost Effective LED Controller
Package C:SOP8
Package Pb- free Packing
P:Pb-free
Blank:Tube A: Taping
Package Marking Information
Y:Year Code WW:Week Code(01-52) ZZZ:Lot Code C:SOP8 Package P:Pb-free Package S:Internal Code(Optional)
©On-Bright Electronics
Confidential -2-
Preliminary datasheet OB_DOC_DS_335000
OB3350
Cost Effective LED Controller
Pin Configuration
VIN GATE GND
CS
1
8
2
7
OB3350
3
6
4
5
PWM OVP COMP FB
No.
Name
1
VIN
2
GATE
3
GND
4
CS
5
FB
6
COMP
7
OVP
8
PWM
I/O Power
I/O GND I/O I/O I/O I/O I/O
.