LX1996 Datasheet, PDF (1/22 Pages) Microsemi Corporation – Multi-string LED Back-light Controller

LX1996
TM
®
Multi-string LED Back-light Controller
PRODUCTION DATASHEET
DESCRIPTION
LX1996 is an integrated white LED Temperature compensated LED current
driver for notebook size displays. It is is accomplished by a dedicated input pin
designed to drive up to six strings of LEDs. (OT) that in conjunction with an external
The LX1996 consists of a boost converter thermistor measures the LED’s ambient
and six precision current sources. It also temperature and thereby prevents over
includes a direct analog light sensor temperature stress to the LEDs by keeping
interface and can be dimmed by a PWM them within their safe operating area.
signal or by application of a DC control Additional features include low sleep
voltage.
mode current (6µA typ.) for extending
Precision current mirror circuitry sets battery time, multi-mode dimming via
all channels to the same current with a ambient light sensor interface, analog
single programming input. The current dimming, direct PWM dimming and
value can be programmed up to 30mA per combination of analog and direct PWM
channel with a single resistor from the dimming for up to a 25000:1 dimming
PRG pin to ground. Channel to channel range.
matching is within ± 0.5 percent typical at The LX1996 is designed to work over a
25°C ambient of the channels mean at the wide input voltage range from 6V to
rated output current.
28Vdc with adjustable over voltage
Unique design features include protection (OVP), and short and open LED
temperature compensated LED current, protection.
and audible noise reduction using The LX1996 comes in a compact thermal
Ultrasonic Pulse Skipping.
efficient 4x4mm 24pin MLPQ package.
KEY FEATURES
• White LED Backlight Controller for
Middle Size Display Panels
• Up to 6 LED Strings with ±0.5%
Precision Current Matching
• Wide Input Voltage Range from 6V
to 28V
• Temperature Compensated LED
Current
• Ultrasonic Pulse Skipping for
audible noise reduction
• Direct Ambient Light Sensor
Interface for Brightness Control
• High Efficiency over Full Dimming
Range
• Low Standby Current
• On-chip Thermal Shut-down
• Over-voltage Protection
• Packaged in a Thermally Efficient
24 pin 4x4mm MLPQ Package
APPLICATIONS
• Notebook & Monitor Displays
• Entertainment Systems
• Automotive Lighting & Panels
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Patents Pending
PRODUCT HIGHLIGHT
6V to 28V
5V
LX1972
Light
Sensor
Multi-Mode Dimming ^PWM
Via Ambient Light
Sensor and/or Direct
PWM Dimming
N/C
VIN
EN
DSEL1
DRV
SRC
PGND
OVP
VLDO
DI
OT
LX1996
DSEL2
RT
PWM
CT
CLF
GND
CS1
CS2
CS3
CS4
CS5
CS6
PRG
5V
Thermistor
Current
Programing
Large LCD Backlight
LED Panel
Temperature
Compensation of
LED Current
PACKAGE ORDER INFO
T_A (°C) ^LQ
Plastic 4x4 mm MLPQ 24-pin
RoHS Compliant / Pb-free
-40 to 85
LX1996ILQ
Note: Available in Tape & Reel. Append the letters “TR” to the part number.
(i.e. LX1996ILQ-TR)
THERMAL DATA
θ_JA = 30 °C/W
THERMAL RESISTANCE-JUNCTION TO AMBIENT
Junction Temperature Calculation: T_J = T_A + (P_D x θ_JA).
The θ_JA numbers are guidelines for the thermal performance of the
device attached to a pc-board system. All of the above assume no
ambient airflow.
Copyright © 2007
Rev. 1.0, 2007-12-14
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
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