DS3881E Maxim Integrated Products, DS3881E Datasheet - Page 18

• Manufacturer Part Number: DS3881E
• Description: Single-channel Automotive CCFL Controller
• Manufacturer: Maxim Integrated Products

Table 2. Status Register 1 (SR1) [SRAM, E0h]
Table 3. Brightness Lamp Current Register (BLC) [SRAM, E3h]
Single-Channel Automotive CCFL Controller
Note 1: Writing to this register has no effect on it.
Note 2: See Figure 8 for more details on how the status bits are set.
Note 3: SR1 is cleared when only the following occurs:
18
BIT
0
1
2
3
4
5
6
7
BIT
0
1
2
3
4
5
6
7
____________________________________________________________________
R/W
R
R
R
R
R
R
R
R
• V
• The SVML or SVMH thresholds are crossed.
• The PDNE hardware pin goes high.
• The PDNE software bit is written to a logic 1.
• The channel is disabled by the CH1D control bit.
CC
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POWER-UP
DEFAULT
drops below the UVLO threshold.
0
0
0
0
0
0
0
0
FACTORY
DEFAULT
0
0
0
0
0
0
0
0
FAULT_RT
SVMH_RT
SVML_RT
FAULT_L
LOUT_L
STO_L
LOC_L
NAME
OV_L
NAME
CH1D
RSVD
SEEB
LC0
LC1
LC2
LC3
LC4
Fault Condition—Real Time. A real-time bit that indicates the current operating status of
channel 1.
0 = Normal condition
1 = Fault condition
Fault Condition—Latched. A latched bit that is set when the channel enters a fault
condition. This bit is cleared when read, regardless of the current state of fault.
Lamp Strike Timeout—Latched. A latched bit that is set when the lamp fails to strike.
This bit is cleared when read.
Overvoltage—Latched. A latched bit that is set when a lamp overvoltage is present for
at least 64 lamp cycles. This bit is cleared when read.
Lamp Out—Latched. A latched bit that is set when a lamp out is detected. This bit is
cleared when read.
Lamp Overcurrent—Latched. A latched bit that is set when a lamp overcurrent is
detected. This bit is cleared when read.
Supply Voltage Monitor Low—Real Time. A real-time bit that reports the comparator
output of the SVML pin.
Supply Voltage Monitor High—Real Time. A real-time bit that reports the comparator
output of the SVMH pin.
These five control bits determine the target value for the lamp current. 11111b is
35% of the nominal level and 00000b is 100% of the nominal level. These control
bits are used for fine adjustment of the lamp brightness.
Channel 1 Disable
0 = Channel 1 enabled
1 = Channel 1 disabled
Reserved. Should be set to 0.
SRAM-Shadowed EEPROM Write Control
0 = Enables writes to EEPROM
1 = Disables writes to EEPROM
FUNCTION
FUNCTION