MICROSEMI LX1691

LX1691
Enhanced Multi-Mode CCFL Controller
®
TM
P RODUCTION D ATA S HEET
KEY FEATURES
DESCRIPTION
Microsemi’s proven and patented
Direct Drive architecture works with
system voltages from 3 volts to more
than 50 volts, limited only by the
external power FET’s that drive the high
voltage transformer.
The LX1691 includes the Microsemi
proven and patented strike method that
allows significant efficiency gains while
guaranteeing strong striking power at all
operating temperatures. Our method
sweeps strike frequency smoothly up to
the unloaded resonant frequency of the
lamp and high voltage transformer.
This, coupled with the LX1691’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.
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 100 ms Power On Delay
ƒ Open Or Shorted Lamp
Regulation & Shutdown
ƒ “On Chip” Full Wave Lamp
Current & Voltage Rectifiers
ƒ 16 Pin TSSOP Package
ƒ Very Stable Oscillator with OnChip Timing Capacitor
ƒ Soft Start-Up Striking
ƒ Enhanced Digital Dimming
Resolution
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Microsemi’s LX1691 is a cost
reduced, enhanced feature set, Direct
Drive CCFL (Cold Cathode Fluorescent
Lamp) Controller. Its architecture is
based on the very popular LX1689. By
limiting VDDP to 5.5V and using
advanced processing, die size and
package pin count is decreased while
improving dimming precision.
LX1691 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 minimum and maximum lamp currents with
resistors. The LX1691 fault shutdown
feature is enhanced to include regulation and shutdown for over voltage
and over current conditions.
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)
BRITE_IN
Lamp Current (mA)
BRITE_IN
+
T
Lamp Current (mA)
BRITE_IN
+
DD_CLK
_
0
T1
T2
T
DD_CLK
T1
LX1691
T
Direct PWM (Analog)
2
+3V
T = 512 / Lamp Frequency
_
T = 512 / DD_CLK Frequency
VDC
VDC
2
+
DD_CLK
T
_
T2
T1
Internal Digital
Lamp Current (mA)
BRITE_IN
0
DD_CLK
T2
External Digital
2
+3V
0
T1
0
+
VDC
VDC
2
_
T2
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
LX1691IPW
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1691IPW-TR)
Copyright © 2003
Rev. 1.2, 8/30/2006
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
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INFORMATION