
General Description
The DS3992 is a low-cost, two-channel controller for
cold-cathode fluorescent lamps (CCFLs) that are used
to backlight liquid crystal displays (LCDs). The DS3992
can drive multiple CCFLs per channel, making it ideal
for 4- and 6-lamp LCD PC monitor and TV applications.
The DS3992 uses a push-pull drive scheme to convert a
DC voltage (5V to 24V) to the high voltage (300V
RMS
to
1400V
RMS
) AC waveform that is required to power the
CCFLs. The push-pull drive scheme uses a minimal
number of external components, which reduces compo-
nent and assembly cost and makes the printed circuit
board (PC board) design easy to implement. The push-
pull drive scheme also provides an efficient DC-to-AC
conversion and produces near-sinusoidal waveforms.
Applications
LCD PC Monitors
LCD-TVs
Features
o
Two-Channel CCFL Controller for Backlighting
LCD Panels for PC Monitors and LCD-TVs
o
Minimal BOM Provides Low-Cost Inverter Solution
o
Per-Channel Lamp Fault Monitoring for Lamp-
Open, Lamp Overcurrent, Failure to Strike, and
Overvoltage Conditions
o
Accurate (±10%) On-Board Oscillator for Lamp
Frequency (40kHz to 80kHz)
o
Accurate (±10%) On-Board Oscillator for DPWM
Burst-Dimming Frequency (90Hz to 220Hz or
180Hz to 440Hz)
o
Device Supply Undervoltage Lockout
o
Inverter Supply Undervoltage Lockout
o
Burst-Dimming Soft-Start Minimizes Audible
Transformer Noise
o
Strike Frequency Boost
o
100% to < 10% Dimming Range
o
4.5V to 5.5V Single-Supply Operation
o
-40°C to +85°C Temperature Range
o
16-Pin SO Package (150 mils)
Ordering Information
D
Two-Channel, Push-Pull CCFL Controller
______________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
1
2
SO-150
TOP VIEW
3
4
5
6
7
8
14
13
16
15
12
11
10
9
OVD2
LCM1
OVD1
GA2
V
CC
V
CC
GA1
GB1
POSC
LOSC
GB2
V
CC
GND
SVM
BRIGHT
LCM2
DS3992
Pin Configuration
Rev 0; 9/06
+Denotes lead-free package.
T&R denotes tape-and-reel package.
PART
TEMP RANGE
DIMMING
FREQUENCY RANGE
BRIGHT POLARITY
PIN-PACKAGE
DS3992Z-09P+
DS3992Z-09N+
DS3992Z-18P+
DS3992Z-18N+
DS3992Z-09P+T&R
DS3992Z-09N+T&R
DS3992Z-18P+T&R
DS3992Z-18N+T&R
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
90Hz to 220Hz
90Hz to 220Hz
180Hz to 440Hz
180Hz to 440Hz
90Hz to 220Hz
90Hz to 220Hz
180Hz to 440Hz
180Hz to 440Hz
Positive
Negative
Positive
Negative
Positive
Negative
Positive
Negative
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
16 SO-16 (150 mils)
Typical Operating Circuits appear at end of data sheet.