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LX1691A
Enhanced Multi-Mode CCFL Controller
®
TM
P RODUCTION D ATA S HEET
KEY FEATURES
DESCRIPTION
Our method sweeps strike frequency
smoothly up to the unloaded resonant
frequency of the lamp and high voltage
transformer. This, coupled with the
LX1691A’s active high output voltage
regulation, produces just enough strike
voltage without generating unpredictable
high voltage spikes that cause arcing and
component failures. Competitive devices
that simply switch to a higher frequency
for striking do not have this “real time”
control over output voltage, and require
much more attention to transformer
design.
The LX1691A is optimized for wide
input voltage applications. It is identical
to the LX1691 except it has a guaranteed
minimum lamp strike interval of one
second to meet notebook and monitor
panel manufacturer’s specifications. The
LX1691A includes feed forward
compensation that provides improved
regulation and transient response over an
7 – 24 volt input supply range. The
LX1691A can also be used with a fixed
input supply and will produce
performance equal to that of the
LX1691.
ƒ Simultaneous Amplitude And
Duty Cycle Dimming Modes
ƒ Resistor programmable min and
max lamp currents
ƒ Digital Dimming Can Synch To
External Or Internal Clocks
ƒ 120 ms Power On Delay
ƒ Open Or Shorted Lamp
Regulation & Shutdown
ƒ “On Chip” Full Wave Lamp
Current Rectifier
ƒ 16 Pin TSSOP Package
ƒ Very Stable Oscillator with OnChip timing capacitor
ƒ Enhanced Digital Dimming
Resolution
ƒ Wide Input Voltage Capable
WWW . Microsemi .C OM
Mircrosemi’s
LX1691A
is
an
enhanced Direct Drive CCFL (Cold
Cathode Fluorescent Lamp) Controller.
Its architecture is based on the LX1691.
LX1691A based inverter modules can
be designed for virtually any CCFL
appliance from digital cameras and
PDA’s to big screen monitors and driver
viewable automotive displays.
New versatile dimming circuitry can
accept digital and analog control inputs
and provides six different dimming
modes that control both lamp current
amplitude and duty cycle, either simultaneously or separately. Designers can
select normal or reverse polarity dimming
and precisely program mini-mum and
maximum lamp currents with resistors.
The LX1691A fault shutdown feature
is enhanced to include regulation and
shutdown for over voltage and over
current conditions.
The LX1691A includes the Microsemi
proven and patented strike method that
allows significant efficiency gains while
guaranteeing strong striking power at all
operating temperatures.
BENEFITS
ƒ Low Component Count / Module
Cost / And Size
ƒ High “Nits/Watt” Efficiency
ƒ Operates Directly From a Single
Li-Ion Cell
ƒ Industries Safest And Highest
Performing Strike Voltage
Generation (Patented)
ƒ Tight Operating Frequency
Tolerance For Easier System
Level RFI Control
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
PRODUCT HIGHLIGHT
Traditional Analog
Lamp Current (mA)
_
T2
VDC
T1
Internal Digital
Lamp Current (mA)
+
BRITE_IN
_
T = 512 / DD_CLK Frequency
Direct PWM (Analog)
T
Lamp Current (mA)
+
BRITE_IN
DD_CLK
_
0
T1
T2
DD_CLK
T
T1
LX1691A
T
DD_CLK
T
2
+3V
T = 512 / 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
_
T2
Four of Six Dimming Modes
PACKAGE ORDER INFO
TA (°C)
MIN VDDP
MAX VDDP
PW
Plastic TSSOP
16-PIN
RoHS Compliant / Pb-free
-40 to +85
2.8V
5.5V
LX1691AIPW
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1691AIPW-TR)
Copyright © 2003
Rev. 1.1, 1/26/2005
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
TM
®
For a complete copy of this data sheet please contact your Microsemi sales representative @
http://www.microsemi.com/contact/contactfind.asp or contact us directly at
[email protected]. Please include your contact information or vcard in your
email.
Copyright
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
WWW . Microsemi .C OM
INFORMATION