
M
4-Wire-Interfaced, 2.5V to 5.5V, 20-Port and
28-Port LED Display Driver and I/O Expander
Figure 2. Two MAX6957s Controlling Seven 7-Segment Displays
P0
P1
P2
P3
P4
P5
P6
P7
P8
P9
P10
P11 P12 P13 P14 P15 P16 P17 P18 P19 P20 P21 P22 P23 P24 P25 P26 P27 P28 P29 P30
P31
P0
P1
P2
P3
P4
P5
P6
P7
P8
P9
P10 P11 P12 P13 P14 P15 P16 P17 P18 P19 P20 P21 P22 P23 P24 P25 P26 P27 P28 P29 P30 P31
7-SEGMENT DIGIT 1
VIRTUAL SEGMENTS
VIRTUAL SEGMENTS
7-SEGMENT DIGIT 5
7-SEGMENT DIGIT 6
7-SEGMENT DIGIT 7
7-SEGMENT DIGIT 2
7-SEGMENT DIGIT 3
7-SEGMENT DIGIT 4
V+
V+
Figure 3. 4-Wire Interface Timing
t
CSH
t
CL
t
CSS
t
CH
t
CSH
CS
SCLK
DIN
DOUT
t
DS
t
DH
t
DV
t
DO
8
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