TLC5930PWPR Datasheet, PDF (18/40 Pages) Texas Instruments – 12-CHANNEL LED DRIVER

TLC5930
SLLS528 – MARCH 2002
PRINCIPLES OF OPERATION
plane brightness adjustment data
Using this packet, the same brightness adjustment data and frequency division data can be written to all
connected devices simultaneously, or different brightness adjustment data and frequency division data can be
written to each device.
The brightness adjustment data latch is configured with 1 x 16 bit, and the current value on each constant output
current can be adjusted in 64 steps as 1 step of 0.94% of current ratio between 100% and 40% when output
current is set to 100% by adjusting external resistor. By using this function, brightness adjustment between
devices can be accomplished by sending required the data from external even though these are mounted on
printed circuit board.
The frequency division ratio register latch is configured with 1 x 4 bit, and the frequency division ratio can be
adjusted in 16 steps between 1:1 and 1:16. This function means that brightness can be adjusted in 16 steps
only by selecting the frequency division ratio, if gray scale clock is set to 16 times the clock (1024x16=16384)
during horizontal scanning time. By using this function, the total panel brightness can be adjusted
simultaneously, and applied to the brightness of day or night.
Table 6. Packet Configuration (32 bit)
ID (Bin)
CMD
(Bin)
xxxxxxxx 00010000
(xx100xxxh)
FREQUENCY
DIVISION
RATIO
1:1
1:2
.
.
.
1:15
1:16
RESERVED
RELATIVE
BRIGHTNESS
RATIO %( )
6.3
12.6
.
.
.
93.8
100.0
DATA
MSB
LSB
MSB
LSB
FREQUENCY
DIVISION DATA
RESERVED
BRIGHTNESS CONTROL DATA
dt [3] dt [2] dt [1] dt [0]
0000
0001
.
.
.
1110
1111
RELATIVE CURRENT
RATIO (%)
40.00
40.94
.
.
.
99.06
100.00
20 (mA)
8.00
8.18
.
.
.
19.82
20.00
40 (mA) dt [5] dt [4] dt [3] dt [2] dt [1] dt [0]
16.00
16.38
.
.
.
39.62
40.00
000000
000001
.
.
.
111110
111111
UDG–02036
18
www.ti.com