LX1691
TM
®
Enhanced Multi-Mode CCFL Controller
P
RODUCTION
D
ATA
S
HEET
DESCRIPTION
KEY FEATURES
Simultaneous Amplitude And
Duty Cycle Dimming Modes
Resistor Programmable Min and
Max Lamp Currents
Digital Dimming Can Synch To
External Or Internal Clocks
100 ms Power On Delay
Open Or Shorted Lamp
Regulation & Shutdown
“On Chip” Full Wave Lamp
Current & Voltage Rectifiers
16 Pin TSSOP Package
Very Stable Oscillator with On-
Chip Timing Capacitor
Soft Start-Up Striking
Enhanced Digital Dimming
Resolution
BENEFITS
Low Component Count / Module
Cost / And Size
High “Nits/Watt” Efficiency
Operates 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
WWW .
Microsemi
.C
OM
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 V
DDP
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 simul-
taneously or separately. Designers can
select normal or reverse polarity
dimming and precisely program mini-
mum and maximum lamp currents with
resistors. The LX1691 fault shutdown
feature is enhanced to include regu-
lation and shutdown for over voltage
and over current conditions.
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.
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
2
Lamp Current (mA)
BRITE_IN
+3V
T2
+
External Digital
2
Lamp Current (mA)
BRITE_IN
+
VDC
0
T1
DD_CLK
T1
VDC
0
_
T2
T
DD_CLK
T = 512 / DD_CLK Frequency
T
_
Internal Digital
2
Lamp Current (mA)
BRITE_IN
+3V
T
+
Direct PWM (Analog)
2
Lamp Current (mA)
BRITE_IN
+
VDC
0
DD_CLK
T
VDC
LX1691
LX1691
_
0
T1
T2
T = 512 / Lamp Frequency
DD_CLK
T1
_
T2
Four of Six Dimming Modes
PACKAGE ORDER INFO
T
A
(°C)
-40 to +85
Copyright
©
2003
Rev. 1.2, 8/30/2006
M
IN
V
DDP
2.8V
M
AX
V
DDP
5.5V
PW
Plastic TSSOP
16-PIN
LX1691IPW
RoHS compliant / Pb-free
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX1691IPW-TR)
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
TM
®
WWW .
Microsemi
.C
OM
INFORMATION
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:
IPGdatasheets@microsemi.com
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
京公网安备 11010802033920号
EEWORLD
