MICROSEMI LX1691BIPW

LX1691B
Enhanced Multi-Mode CCFL Controller
®
TM
P RELIMINARY D ATA S HEET
KEY FEATURES
Wide Input Voltage Capable
Simultaneous Amplitude And
Duty Cycle Dimming Modes
Resistor programmable min
and max lamp currents
Digital Dimming Can Synch To
External Or Internal Clocks
120 ms Power On Delay
Open Or Shorted Lamp
Regulation & Shutdown
“On Chip” Full Wave Lamp
Current Rectifier
16 Pin TSSOP Package
Very Stable Oscillator with OnChip timing capacitor
Enhanced Digital Dimming
Resolution
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DESCRIPTION
The LX1691B is an enhanced Direct modes that control lamp current amplitude
Drive CCFL (Cold Cathode Fluorescent and duty cycle simultaneously or separately.
Lamp) Controller. Its architecture is based on Designers can select normal or reverse
the LX1691. The LX1961B is optimized for polarity dimming and precisely program
wide input voltage applications. It is similar minimum and maximum lamp currents with
to the LX1691 except it has a guaranteed resistors. Fault protection includes open
minimum lamp strike interval of one second1 lamp voltage regulation and shutdown for
to meet notebook and monitor panel over voltage and over current conditions.
manufacturer’s specifications.
The “B” The LX1691B employs Microsemi’s proven
version also adds feed forward input voltage and patented strike method that allows
sensing to enhance transient response when significant
efficiency
gains
while
used in inverters that derive lamp power guaranteeing strong striking power at all
from unregulated input supplies and operating temperatures.
Our method
batteries.
sweeps strike frequency smoothly up to the
The LX1691B can also be used with unloaded resonant frequency of the lamp
fixed input supplies where it produces and high voltage transformer. This, coupled
performance equal to the LX1691.
with the LX1691B’s active high output
LX1691B based inverter modules can be voltage regulation, produces just enough
designed for virtually any CCFL appliance strike
voltage
without
generating
from digital cameras and PDA’s to big unpredictable high voltage spikes that cause
screen monitors and driver viewable arcing and component failures. Competitive
automotive displays.
devices that simply switch to a higher
New versatile dimming circuitry can
frequency for striking do not have this “real
accept digital and analog control inputs and
time” control over output voltage, and
provides six different dimming
require much more attention to transformer
design.
BENEFITS
Low Component Count /
Module Cost / And Size
High “Nits/Watt” Efficiency
Can Operate Directly From a
Single Li-Ion Cell
Industries Safest And Highest
Performing Strike Voltage
Generation (Patented)
Tight Operating Frequency
Tolerance For Easier System
Level RFI Control
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IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
Protected by U.S. Patents: 5,615,093; 5,923,129; 5,930,121; 6,198,234; Patents Pending
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PRODUCT HIGHLIGHT
Traditional Analog
Lamp Current (mA)
_
T2
VDC
T1
Internal Digital
Lamp Current (mA)
+
BRITE_IN
T
DD_CLK
T
_
T = 512 / DD_CLK Frequency
Direct PWM (Analog)
T
Lamp Current (mA)
+
BRITE_IN
2
+3V
DD_CLK
T = 256 / Lamp Frequency
+
VDC
VDC
2
Lamp Current (mA)
BRITE_IN
VDC
0
DD_CLK
T2
External Digital
2
+3V
0
T1
0
+
BRITE_IN
2
_
0
T1
T2
DD_CLK
T
T1
_
T2
LX1691B
Four of Six Dimming Modes
PACKAGE ORDER INFO
TA (°C)
MIN VDDP
MAX VDDP
-40 to +85
2.8V
5.5V
PW
Plastic TSSOP
16-PIN
RoHS compliant / Pb-free
LX1691BIPW
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1691BIPW-TR)
1
If the lamp frequency is less than 115Khz.
Copyright © 2005
Rev. 0.4a, 3/8/2005
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
TM
®
Thank you for your interest in Microsemi® IPG products.
The full data sheet for this device contains proprietary information.
To obtain a copy, please contact your local Microsemi sales representative. The
name of your local representative can be obtained at the following link
http://www.microsemi.com/contact/contactfind.asp
or
Contact us directly by sending an email to:
[email protected]
Be sure to specify the data sheet you are requesting and include your company
name and contact information and or vcard.
We look forward to hearing from you.
Copyright
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
WWW . Microsemi .C OM
INFORMATION