Datasheet

DS3881
Single-Channel Automotive CCFL Controller
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Table 8. Lamp Current Overdrive Control Register (LCOC) [Shadowed-EEPROM, F7h]
BIT R/W
FACTORY
DEFAULT
NAME FUNCTION
LAMP CURRENT OVERDRIVE SELECT
LCO2 LCO1 LCO0 SELECTED LAMP CURRENT OVERDRIVE
0 0 0 Nominal Current + 12.50%
0 R/W 0 LCO0
0 0 1 Nominal Current + 25.00%
0 1 0 Nominal Current + 37.50%
0 1 1 Nominal Current + 50.00%
1 R/W 0 LCO1
1 0 0 Nominal Current + 62.50%
1 0 1 Nominal Current + 75.00%
1 1 0 Nominal Current + 87.50%2 R/W 0 LCO2
1 1 1 Nominal Current + 100.00%
3 R/W 0 LCOE
Lamp Current Overdrive Enable. Logically ORed with the LCO pin.
0 = Lamp operated with nominal current setting.
1 = Lamp overdrive invoked.
AUTOMATIC LAMP CURRENT OVERDRIVE TIMEOUT SELECT
TO3 TO2 TO1 TO0
SELECTED TIMEOUT
IN LAMP FREQUENCY
CYCLES
EXAMPLE TIMEOUT IF
LAMP FREQUENCY IS
50kHz
4 R/W 0 TO0
0 0 0 0 Disabled —
0001 1 x 2
22
1.4 min
0010 2 x 2
22
2.8 min
0011 3 x 2
22
4.2 min
0100 4 x 2
22
5.6 min
5 R/W 0 TO1
0101 5 x 2
22
7.0 min
0110 6 x 2
22
8.4 min
0111 7 x 2
22
9.8 min
1000 8 x 2
22
11.2 min
1001 9 x 2
22
12.6 min
6 R/W 0 TO2
1 0 1 0 10 x 2
22
14.0 min
1 0 1 1 11 x 2
22
15.4 min
1 1 0 0 12 x 2
22
16.8 min
1 1 0 1 13 x 2
22
18.2 min
1 1 1 0 14 x 2
22
19.6 min
7 R/W 0 TO3
1 1 1 1 15 x 2
22
21.0 min