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

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)

Two-Channel, Push-Pull CCFL Controller

______________________________________________

Maxim Integrated Products

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

GA1

GB1

POSC

LOSC

GB2

GND

SVM

BRIGHT

LCM2

DS3992

Pin Configuration

Rev 0; 9/06

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.

+

Denotes lead-free package.

T&R denotes tape-and-reel package.

Ordering Information

PART

TEMP RANGE

DIMMING

FREQUENCY RANGE

BRIGHT POLARITY

PIN-PACKAGE

DS3992Z-09P+

-40°C to +85°C

90Hz to 220Hz

Positive

16 SO-16 (150 mils)

DS3992Z-09N+

-40°C to +85°C

90Hz to 220Hz

Negative

16 SO-16 (150 mils)

DS3992Z-18P+

-40°C to +85°C

180Hz to 440Hz

Positive

16 SO-16 (150 mils)

DS3992Z-18N+

-40°C to +85°C

180Hz to 440Hz

Negative

16 SO-16 (150 mils)

DS3992Z-09P+T&R

-40°C to +85°C

90Hz to 220Hz

Positive

16 SO-16 (150 mils)

DS3992Z-09N+T&R

-40°C to +85°C

90Hz to 220Hz

Negative

16 SO-16 (150 mils)

DS3992Z-18P+T&R

-40°C to +85°C

180Hz to 440Hz

Positive

16 SO-16 (150 mils)

DS3992Z-18N+T&R

-40°C to +85°C

180Hz to 440Hz

Negative

16 SO-16 (150 mils)

Typical Operating Circuits appear at end of data sheet.