Data Sheet AS1100
8x8 LED Dot Matrix Driver
The example in Figure 3 uses the AS1100 to drive an 8x8 LED dot matrix. The LED columns have common cathode
and are connected to the DIG0-7 outputs. The rows are connected to the segment drivers. Each of the 64 LEDs can
be addressed separately. The columns are selected via the digits as shown in Table 2. The decode mode register
(0xX9) has to be programmed to ‘00000000’ as stated in Table 4. The single LEDs in a column can be addressed as
stated in Table 6, where D0 corresponds to segment G and d/ to segment DP. For a multiple digit dot matrix several
AS1100 have to be cascaded.
8x8 LED Dot
8x8 LED Dot
SEG G
SEG F
SEG E
SEG D
SEG C
SEG B
SEG A
SEG DP
SEG G
SEG F
SEG E
SEG D
SEG C
SEG B
SEG A
SEG DP
Diode Arrangement
DIG 0
SEG A-G DIG 0-
DIG 7
DIG 0
DIG 7
SEG A-G DIG 0-
SEP DP
24
SEP DP
DOUT
VBAT
VBAT
19
19
18
1
1
VDD
VDD
DIN
DIN
12
1
12
1
µP
LOA
CLK
GND
LOA
CLK
9.53k
9.53k
18
9
9
ISET
ISET
GND
GND
GND
4
4
Figure 3: Application example as LED dot matrix driver
Cascading Drivers
The AS1100 can be cascaded as well. The DOUT pin must be connected to the DIN pin of the following AS1100.
Thermal Resistance (θJA
+75°C/W
)
Package
24 Narrow DIP
24 Wide SO
+85°C/W
Maximum Junction Temperature (TJ) = +150°C
Maximum Ambient Temperature (TA) = +85°C
Table 13: Package thermal resistance data
Revision 1.32, Oct. 2004
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