Datasheet

DS3881
Single-Channel Automotive CCFL Controller
16 ____________________________________________________________________
MOSFET GATE DRIVERS ENABLED
DEVICE AND
INVERTER SUPPLIES
AT PROPER LEVELS?
STRIKE LAMP
[RAMP AND REGULATE TO
OVD THRESHOLD]
FAULT WAIT
[1024 LAMP CYCLES]
LAMP STRIKE TIMEOUT
[SEE REGISTER SSP1]
RUN LAMP
[REGULATE LAMP
CURRENT BOUNDED BY
LAMP VOLTAGE]
LAMP OUT TIMEOUT
[SEE REGISTER SSP1]
INCREMENT FAULT
COUNTER / SET
FAULT_RT STATUS BIT
FAULT COUNTER = 15?
FAULT STATE
[ACTIVATE FAULT OUTPUT]
LAMP OVERCURRENT
[INSTANTANEOUS IF
ENABLED BY THE
LOCE BIT AT CR1.0]
NO
YES
AUTORETRY ENABLED?
[ARD BIT AT CR1.5]
NO
YES
YES
OVERVOLTAGE
[64 LAMP CYCLES]
SET LOUT_L
STATUS BIT
SET OV_L
STATUS BIT
SET STO_L
STATUS BIT
SET LOC_L
STATUS BIT
CLEAR
FAULT_RT
STATUS BIT
IF LAMP REGULATION
THRESHOLD IS MET
RESET FAULT COUNTER
AND FAULT OUTPUT
SET FAULT_L
AND FAULT_RT
STATUS BITS
Figure 8. Fault-Handling Flowchart