www.austriamicrosystems.com/LED-Driver-ICs/AS1106_07

Revision 2.29

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AS1106, AS1107

Datasheet - A p p l i c a t i o n I n f o r m a t i o n

9.4 8x8 LED Dot Matrix Driver

The application example in Figure 14 shows the AS1106 as an 8x8 LED dot matrix driver.

The LED columns have common cathodes 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 listed in Table 7 on page 9.

The Decode Enable Register (see page 10) must be set to ‘00000000’ as described in Table 9 on page 10. Single LEDs in a column can be

addressed as described in Table 12 on page 11, where bit D0 corresponds to segment G and bit D7 corresponds to segment DP.

Note:

For a multiple-digit dot matrix, multiple AS1106 devices must be cascaded.

Figure 14. Application Example as LED Dot Matrix Driver

9.5 Cascading Drivers

The example in Figure 14 drives 2 dot matrix digits using a 4-wire microprocessor interface. All Scan-Limit Registers should be set to the same

value so that one display will not appear brighter than the other.

For example, to display 12 digits, set both Scan-Limit Registers to display 6 digits so that both displays have a 1/6 duty cycle per digit. If 11 digits

are needed, set both Scan-Limit Registers to display 6 digits and leave one digit unconnected. Otherwise, if one driver is set to display 6 digits

and the other to display 5 digits one display will appear brighter because its duty cycle per digit will be 1/5 and the other display’s duty cycle will

be 1/6.

Note:

Refer to No-Op Register (0xX0) on page 13 for additional information.

SEG G

DIG0:7

ISET

DIN

GND

GND

LOAD/CSN

CLK

VDD

SEG A:G

SEG DP

9.53k

Ω

DIG0:7

ISET

DIN

GND

GND

LOAD/CSN

CLK

VDD

SEG A:G

SEG DP

9.53k

Ω

DOUT

8x8 LED Dot Matrix

8x8 LED Dot Matrix

Diode Arrangement

VBAT

VBAT

Micro-

Processor

SEG A

SEG DP

SEG B

SEG C

SEG D

SEG E

SEG F

SEG G

SEG A

SEG DP

SEG B

SEG C

SEG D

SEG E

SEG F

AS1106/

AS1107

AS1106/

AS1107