DS3988 Datasheet, PDF (1/23 Pages) Maxim Integrated Products – 8-Channel Cold-Cathode Fluorescent Lamp Controller

Rev 0; 4/05
8-Channel Cold-Cathode
Fluorescent Lamp Controller
General Description
The DS3988 is an 8-channel controller for cold-cathode
fluorescent lamps (CCFLs) used to backlight liquid
crystal displays (LCDs) in TV and PC monitor applica-
tions. The DS3988 supports configurations of 1 to 8
lamps, and multiple DS3988 controllers can be cascad-
ed to support applications requiring more than 8 lamps.
LCD Televisions
LCD PC Monitors
Applications
Ordering Information
PART
TEMP RANGE
DS3988T
-40°C to +85°C
DS3988T+
-40°C to +85°C
+Denotes lead-free package.
PIN-PACKAGE
48 TQFP
48 TQFP
Pin Configuration
TOP VIEW
GA1 1
GB1 2
LCM1 3
OVD1 4
GA2 5
GB2 6
LCM2 7
OVD2 8
GA3 9
GB3 10
LCM3 11
OVD3 12
DS3988
36 OVD8
35 LCM8
34 GB8
33 GA8
32 OVD7
31 LCM7
30 GB7
29 GA7
28 OVD6
27 LCM6
26 GB6
25 GA6
48-LEAD TQFP
7 x 7 x 1.0mm
Features
♦ High-Density CCFL Controller for LCD TV and PC
Monitor Backlights
♦ Can Be Easily Cascaded to Support More Than
8 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
♦ 48-Lead TQFP (7mm x 7mm) 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.
Typical Operating Circuit appears at end of data sheet.
______________________________________________ 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.