G2542 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – 6-Channels 40V White LED Driver with Boost Regulator

Global Mixed-mode Technology
G2542
6-Channels 40V White LED Driver
with Boost Regulator
Features
„ Wide 2.7V to 5.5V Input Supply Range
„ 600KHz Fixed Frequency
„ 40V/2A, 0.2Ω n-channel MOSFET
„ Maximum Programmable LED Channel Current
30mA
„ Current accuracy ±3% and current balance ±2%
„ 100Hz~25kHz PWM Dimming
„ PWM to DC Dimming
„ Protection
Š Input Under-Voltage Protection
Š Over Current Protection
Š Over Voltage Protection
Š Thermal Protection
„ RoHs Compliant
„ TQFN4X4-20 Package
Applications
„ UMPC and Notebook Computer Backlight
Ordering Information
ORDER
NUMBER
TEMP.
RANGE
PACKAGE
(Green)
PACKING
G2542R91U
2542
-40°C to +85°C TQFN4X4-20
Note:R9: TQFN4X4-20
1: Bonding Code
U: Tape & Reel
General Description
The G2542 is a high-efficiency 6-channel white LED
driver. It is designed for LCD panel that employs an LED
array as the lighting source. An integrated switch current
mode boost controller drives six strings in parallel and
supports up to 10 pieces of LEDs per string.
The G2542 automatically regulated supply voltage for
the LED light bars without the need to calculate the
output for different LED types. It also integrates a 40V
n-channel MOSFET that provides high output power.
The 6-channel current driver is ideal for constant cur-
rent driving, and well matched less than 3%. To set
the maximum driving current, the ISET pin is used to
determine reference current. Each channel of the cur-
rent drivers is set to 800 times of this reference current.
A PWM pin can be used to perform PWM dimming
from the range of 100Hz to 25kHz.
The MODE pin in G2542 is used to set the dimming
mode. If MODE pin set to floating, the dimming mode
is in the PWM mode, the current driver ON/OFF is
synchronized with the PWM signal. If Mode pin set to
AGND, PWM and ILED current is set at PWM duty
multiplied by ISET current when PWM duty ≥ 25%. If
the PWM duty <25%, the ILED current is fixed at
0.25xISET, and the dimming duty is 4 x PWM duty. If
MODE set to VDC, the dimming mode operated in the
Pure DC mode, the current-source outputs are DC
dimming and the PWM duty cycle modulates the am-
plitude of the currents. Open LED-string automatically
disable the channel from entering over voltage protec-
tion.
Pin Configuration
Typical Application Circuit
G2542
EN 1
NC 2
ISET 3
MODE 4
AGND 5
Thermal
Pad
15 LX
14 PGND
13 PGND
12 OVP
11 CS1
TQFN4X4-20
Note: Recommend connecting the Thermal Pad to
the Ground for excellent power dissipation.
VIN
C_VIN
R_VIN
L1
D1
LX _OVP
VIN
R_OVP2
R_OVP1
C_OUT
VCC
C_VCC
VDC
EN
MODE
R_C1 ^CC2
C_C1
PWM
G2542
COMP LED1
LED2
LED3
ISET LED4
R_ISET
LED5
LED6
AGND PGND
V_OUT
40V MAX
Ver: 0.2
Aug 12, 2013
TEL: [phone]
http://www.gmt.com.tw
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