Datasheet

DS3881
Single-Channel Automotive CCFL Controller
8 _____________________________________________________________________
Functional Diagrams
GA1
MOSFET
GATE
DRIVERS
GB1
OVD1
OVERVOLTAGE
DETECTION
LAMP FREQUENCY
INPUT/OUTPUT
[20.48MHz ~ 51.20MHz]
I
2
C DEVICE
CONFIGURATION AND
CONTROL PORT
22.5Hz TO 440Hz
EXTERNAL RESISTOR
LAMP FREQUENCY SET
GND
SINGLE
CCFL
CONTROLLER
EXTERNAL RESISTOR
DPWM FREQUENCY
SET/DPWM CLOCK INPUT
DPWM SIGNAL
INPUT/OUTPUT
ANALOG BRIGHTNESS
CONTROL
SVMH
SUPPLY VOLTAGE
MONITOR—HIGH
[40kHz ~ 100kHz]
System
Enable /
POR
EEPROM
8 BYTE USER MEMORY
CONTROL REGISTERS
FAULT
CHANNEL FAULT
CHANNEL ENABLE
SDA
SCL
LSYNC
LOSC
PSYNC
BRIGHT
DPWM
SIGNAL
2.0V
STATUS REGISTERS
PDN
LCO
2.0V
SVML
SUPPLY VOLTAGE
MONITOR—LOW
STEP
STEP LAMP FREQUENCY
UP OR DOWN
40kHz TO 100kHz
OSCILLATOR (±5%)
LCM1
LAMP CURRENT
MONITOR
V
CC
[4.75V TO 5.25V]
x512
PLL
I
2
C
INTERFACE
SYSTEM
ENABLE/
POR
FAULT
HANDLING
22.5Hz TO
440Hz
OSCILLATOR
(±5%)
POSC
A0/A1
GND_S
DPSS BIT
AT CR1.3
LFSS BIT
AT CR1.2
UVLO
VREF
MUX
POSCS BIT
AT CR1.1
MUX
RGSO BIT
AT CR1.4
MUX
DPSS BIT
AT CR1.3
RAMP
GENERATOR
DS3881
Figure 1. Functional Diagram