RangeMAX™
TM
®
LX1688
Multiple Lamp CCFL Controller
P
RODUCTION
D
ATA
S
HEET
TABLE 1
WWW .
Microsemi
.C
OM
Pin BEPOL
V
DD
FLOAT
V
SS
ENABLE POLARITY
+ (HI = CHIP_ON, LOW = CHIP_OFF
+ (HI = CHIP_ON, LOW = CHIP_OFF)
- (LOW = CHIP_ON, HI = CHIP_OFF)
DIMMING POLARITY*
CONVENTIONAL
REVERSE
REVERSE
* Conventional polarity means that the lamp brightness increases with increasing voltage on the BRITE pin.
Reverse polarity means that brightness decreases with increasing voltage
OPERATIONAL MODES
Controller
Mode
Master
Controller
Operation
Run
Striking
Fault
Run
Slave
Striking
Fault
Input Pin:
OLSNS
> 0.6V
< 0.2V
X
> 0.6V
< 0.2V
X
Input Pin:
SLAVE
VSS
VSS
VSS
VDD
VDD
VDD
Output Pin:
FAULT
L
L
H
L
L
H
Pin: RMP_RST
Output: F
INT
Output: F
INT
Output: F
INT
Input: F
EXT
Input: F
EXT
Input: F
EXT
Pin: A_SYNC
Output: F
INT
/ 2
Output: F
INT
/ 2
Output: F
INT
/ 2
Input: F
EXT
/ 2
Input: F
EXT
/ 2
Input: F
EXT
/ 2
Lamp
Frequency
F
INT
/ 2
Ramping up /
down
Off
F
EXT
/ 2
Ramping up /
down
Off
SIMPLIFIED BLOCK DIAGRAM
ISNS VSNS
F
EXT
/2
ERROR AMP
TFF R
PWR_ GD
PWR_ BD
1.25V
VAMP
PWR_ GD
FAULT
VOLTAGE
COMPARATOR
VCOMP ICOMP
V
DD_P
Q
PHA_SYNC
Q
A OUT
T
SLAVE
RMP_RST
F
INT
RAMP RUN
GENERATOR
STRIKE
GENERATOR
PWR_BD
FAULT
OUTPUT
STEERING
LOGIC
Q
B OUT
VSS_P
F
EXT
300mV
IAMP
CURRENT
COMPARATOR
1V
200K
+
-
100K
100K
1V
+
-
BRT
100K
0-2V
800mV
600mV
BRITE
+
-
2.5
V
100K
IGNITE
OLSNS
CPW 1
CPW 2
BEPOL
1M
0.5
V
1M
PWR_ BD
VDD
6 BIT
COUNTER
TRI WAVE
GEN
TRI_C
B
LOCK
D
IAGRAM
B
LOCK
D
IAGRAM
POLARITY
DECODE
BIAS GEN
UVLO
PWR_GD
FAULT
ENABLE
VDDSW
TTL
BUF
INTERNAL VDD
PWR_BD
TTL
BUF
FAULT
VSS
LX1688
VSS
VDD
I_R
CPOR
Figure –
Simplified Block Diagram
Copyright
©
2001
Rev. 1.2, 2006-03-09
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
MICROSEMI [ MICROSEMI CORPORATION ]
