MAX1996AETI+ Maxim Integrated Products, MAX1996AETI+ Datasheet - Page 8

• Manufacturer Part Number: MAX1996AETI+
• Description: Display Drivers CCFL Backlight Controller
• Manufacturer: Maxim Integrated Products

Specifications of MAX1996AETI+

• Lead Free Status / Rohs Status: Details

High-Efficiency, Wide Brightness
Range, CCFL Backlight Controller
8
9, 10, 11, 23
_______________________________________________________________________________________
PIN
12
13
14
15
16
17
18
19
20
21
22
24
25
26
27
28
7
8
CTL/SCL
SH/SUS
NAME
PGND
BATT
BST1
BST2
N.C.
GH1
GH2
CCV
V
GL2
GL1
VFB
V
LX1
LX2
CCI
IFB
DD
CC
Brightness Control and Serial Clock Input. In analog interface mode, pin 7 is a CCFL brightness
control input. CTL varies from 0V to REF to linearly control lamp brightness. In SMBus interface
mode, SCL is an SMBus serial clock input.
Shutdown and Suspend Mode Control. In analog interface mode, pin 8 is an active-low shutdown
input. In SMBus interface mode, pin 8 is an SMBus suspend control input.
No Connection. Not internally connected.
Power Supply for Gate Drivers. Connect V
with a 0.1µF capacitor to PGND.
Power Ground. Gate-driver current flows through this pin.
Low-Side FET NL2 Gate-Driver Output
Low-Side FET NL1 Gate-Driver Output
High-Side FET NH1 Gate-Driver Output
Switching Node Connection. LX1 is the internal lower supply rail for the GH1 high-side gate driver.
LX1 is also the sense input to the current comparators.
High-Side FET NH1 Driver Bootstrap Input. Connect BST1 through a diode to V
0.1µF capacitor to LX1 (Figure 1).
High-Side FET NH2 Driver Bootstrap Input. Connect BST2 through a diode to V
0.1µF capacitor to LX2 (Figure 1).
Switching Node Connection. LX2 is the internal lower supply rail for the GH2 high-side gate driver.
LX2 is also the sense input to the current comparators.
High-Side FET NH2 Gate-Driver Output
Lamp-Output Feedback-Sense Input. The average value on VFB is regulated during startup and
open-lamp conditions to 0.5V by controlling the on-time of high-side switches. A capacitive voltage-
divider between the CCFL lamp output and GND is sensed to set the maximum average lamp
output voltage.
Lamp Current-Sense Input. The voltage on IFB is used to regulate the lamp current. If the IFB input
falls below 150mV for 1s, then the MAX1996A signals an open-lamp fault.
Current-Loop Compensation Pin. CCI is the output of the current-loop transconductance amplifier
(GMI) that regulates the CCFL current. The CCI voltage controls the time interval in which full-
bridge applies the input voltage (BATT) to transformer network. Connect CCI to GND through a
0.1µF capacitor. CCI is internally discharged to GND in shutdown.
Voltage-Loop Compensation Pin. CCV is the output of the voltage-loop transconductance amplifier
(GMV) that regulates the maximum average secondary transformer voltage. Connect CCV to GND
with a 10nF capacitor. The CCV voltage controls the time interval that the full bridge applies the
input voltage (BATT) to transformer network. CCV is internally discharged to GND in shutdown.
Supply Input. Input to the internal 5.3V linear regulator that provides power (V
Bypass BATT to GND with a 0.1µF capacitor.
5.3V Linear-Regulator Output. V
with a 0.47µF ceramic capacitor. V
CC
CC
is the supply voltage for the MAX1996A. Bypass V
can also be connected to BATT if V
DD
FUNCTION
to the output of the linear regulator (V
Pin Description (continued)
BATT
CC
< 5.5V.
DD
DD
) to the chip.
and through a
and through a
CC
). Bypass V
CC
to GND
DD