DS3988T+T&R;

Rev 0; 4/05 8-Channel Cold-Cathode Fluorescent Lamp Controller 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 applications. The DS3988 supports configurations of 1 to 8 lamps, and multiple DS3988 controllers can be cascaded to support applications requiring more than 8 lamps. Applications LCD Televisions LCD PC Monitors Ordering Information PART TEMP RANGE PIN-PACKAGE DS3988T -40°C to +85°C 48 TQFP DS3988T+ -40°C to +85°C 48 TQFP +Denotes lead-free package. Pin Configuration FAULT SCL SDA 37 38 39 40 41 42 43 GND POSC PSYNC A0 LOSC LSYNC 45 44 SVM BRIGHT 46 VCC 47 1 36 2 35 3 34 GA2 GB2 5 6 31 LCM2 OVD2 7 30 8 29 GA3 9 28 GB3 LCM3 10 27 11 26 OVD3 12 25 33 4 32 ♦ 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 OVD8 LCM8 GB8 GA8 OVD7 LCM7 GB7 GA7 OVD6 LCM6 GB6 GA6 ♦ 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 24 23 22 21 20 ♦ Minimal External Components GB5 LCM5 OVD5 VCC GND 19 18 16 17 OVD4 GND GA5 14 15 13 DS3988 GA4 GB4 LCM4 ♦ Can Be Easily Cascaded to Support More Than 8 Lamps ♦ Programmable Soft-Start Minimizes Audible Transformer Noise GA1 GB1 LCM1 OVD1 GND ♦ High-Density CCFL Controller for LCD TV and PC Monitor Backlights ♦