DS3984 Datasheet, PDF (1/24 Pages) Dallas Semiconductor – 4-Channel Cold-Cathode Fluorescent Lamp Controller

Rev 0; 4/05
4-Channel Cold-Cathode
Fluorescent Lamp Controller
General Description
The DS3984 is a 4-channel controller for cold-cathode
fluorescent lamps (CCFLs) used to backlight liquid
crystal displays (LCDs) in TV and PC monitor applica-
tions. The DS3984 supports configurations of 1 to 4
lamps, and multiple DS3984 controllers can be cascad-
ed to support applications requiring more than 4 lamps.
LCD Televisions
LCD PC Monitors
Applications
Ordering Information
PART
TEMP RANGE
DS3984T
-40°C to +85°C
DS3984T+
-40°C to +85°C
DS3984Z
-40°C to +85°C
DS3984Z+
-40°C to +85°C
+Denotes lead-free package.
PIN-PACKAGE
32 TQFP
32 TQFP
28 SO.300
28 SO.300
Pin Configurations
TOP VIEW
LOSC 1
A0 2
PSYNC 3
POSC 4
BRIGHT 5
SVM 6
GA1 7
GB1 8
LCM1 9
OVD1 10
GA2 11
GB2 12
LCM2 13
OVD2 14
DS3984
28-SO-300
28 LSYNC
27 FAULT
26 SCL
25 SDA
24 OVD4
23 LCM4
22 GB4
21 GA4
20 OVD3
19 LCM3
18 GB3
17 GA3
16 V_CC
15 GND
Pin Configurations continued at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
Features
♦ High-Density CCFL Controller for LCD TV and PC
Monitor Backlights
♦ Can Be Easily Cascaded to Support More Than
4 Lamps
♦ Minimal External Components
♦ Analog Brightness Control
♦ Per-Channel Lamp Control Ensures Equal
Brightness Among Lamps and Maximizes Lamp
Life
♦ Gate Driver Phasing Minimizes DC Supply Current
Surges
♦ Per-Channel Lamp Fault Monitoring for Lamp
Open, Lamp Overcurrent, Failure to Strike, and
Overvoltage Conditions
♦ Accurate (±5%) Independent On-Board Oscillators
for Lamp Frequency (40kHz to 80kHz) and DPWM
Burst Dimming Frequency (22.5Hz to 440Hz)
♦ Can Be Synchronized to External Sources for the
Lamp and DPWM Frequencies
♦ <10% to 100% Dimming Range
♦ Programmable Soft-Start Minimizes Audible
Transformer Noise
♦ I²C-Compatible Serial Port and On-Board
Nonvolatile (NV) Memory Allow Device
Customization
♦ 8-Byte NV User Memory for Storage of Serial
Numbers and Date Codes
♦ 4.5V to 5.5V Single-Supply Operation
♦ -40°C to +85°C Temperature Range
♦ 32-Lead TQFP (7mm x 7mm) Package or
28-Pin SO (300 mils) Package
I²C is a trademark of Philips Corp. Purchase of I²C compo-
nents from Maxim Integrated Products, Inc., or one of its subli-
censed Associated Companies, conveys a license under the
Philips I²C Patent Rights to use these components in an I²C
system, provided that the system conforms to the I²C Standard
Specification as defined by Philips.
______________________________________________ Maxim Integrated Products 1
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.