19-0197; Rev 1; 1/95
CCFL Ba c k lig h t a n d
LCD Co n t ra s t Co n t ro lle rs
3/MAX754
_______________Ge n e ra l De s c rip t io n
____________________________Fe a t u re s
♦ Drives Backplane and Backlight
♦ 4V to 30V Battery Voltage Range
♦ Low 500µA Supply Current
The MAX753/MAX754 drive cold-cathode fluorescent
lamps (CCFLs) and provide the LCD backplane bias
(contrast) power for color or monochrome LCD panels.
These ICs are designed specifically for backlit note-
book-computer applications.
♦ Digital or Potentiometer Control of CCFL
Brightness and LCD Bias Voltage
Both the backplane bias and the CCFL supply can be
shut down independently. When both sections are shut
down, supply current drops to 25µA. The LCD contrast
and CCFL brightness can be adjusted by clocking sep-
arate digital inputs or using external potentiometers.
LCD contrast and backlight brightness settings are pre-
served in their respective counters while in shutdown.
On p owe r-up , the LCD c ontra s t c ounte r a nd CCFL
brightness counter are set to one-half scale.
♦ Negative LCD Contrast (MAX753)
♦ Positive LCD Contrast (MAX754)
♦ Independent Shutdown of Backlight and
Backplane Sections
♦ 25µA Shutdown Supply Current
The ICs are powered from a regulated 5V supply. The
magnetics are connected directly to the battery, for
maximum power efficiency.
______________Ord e rin g In fo rm a t io n
The CCFL driver uses a Royer-type resonant architec-
ture. It can provide from 100mW to 6W of power to one
or two tubes. The MAX753 provides a negative LCD
bias voltage; the MAX754 provides a positive LCD bias
voltage.
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
16 Plastic DIP
16 Narrow SO
Dice*
MAX753CPE
MAX753CSE
MAX753C/D
MAX753EPE
MAX753ESE
MAX754CPE
MAX754CSE
MAX754C/D
MAX754EPE
MAX754ESE
16 Plastic DIP
16 Narrow SO
16 Plastic DIP
16 Narrow SO
Dice*
________________________Ap p lic a t io n s
Notebook Computers
Palmtop Computers
Pen-Based Data Systems
16 Plastic DIP
16 Narrow SO
Personal Digital Assistants
Portable Data-Collection Terminals
* Contact factory for dice specifications.
__________________P in Co n fig u ra t io n
TOP VIEW
V
LFB
DD
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
LADJ
LON
CON
BATT
LX
LDRV
PGND
CDRV
CS
MAX753
MAX754
CADJ
GND
REF
CFB
CC
DIP/SO
Block Diagram located at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
Ca ll t o ll fre e 1 -8 0 0 -9 9 8 -8 8 0 0 fo r fre e s a m p le s o r lit e ra t u re .