MAX6956 Maxim, MAX6956 Datasheet - Page 16
![no-image](/images/no-image-200.jpg)
MAX6956
Manufacturer Part Number
MAX6956
Description
2-Wire-Interfaced / 2.5V to 5.5V / 20-Port or 28-Port LED Display Driver and I/O Expander
Manufacturer
Maxim
Datasheet
1.MAX6956.pdf
(27 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
MAX6956AAI+
Manufacturer:
Maxim Integrated Products
Quantity:
1 970
Company:
Part Number:
MAX6956AAI+T
Manufacturer:
MAXIM
Quantity:
769
Company:
Part Number:
MAX6956AAX+
Manufacturer:
Maxim Integrated Products
Quantity:
28 985
Part Number:
MAX6956AAX+
Manufacturer:
MAXIM/美信
Quantity:
20 000
Company:
Part Number:
MAX6956AAX/V+T
Manufacturer:
DALLAS
Quantity:
162
Company:
Part Number:
MAX6956ATL
Manufacturer:
MAXIM
Quantity:
30
The mask register contains 7 mask bits, which select
which of the seven ports P24–P30 are to be monitored
(Table 15). Set the appropriate mask bit to enable that
port for transition detect. Clear the mask bit if transitions
on that port are to be ignored. Transition detection
works regardless of whether the port being monitored is
set to input or output, but generally, it is not particularly
useful to enable transition detection for outputs.
To use transition detection, first set up the mask register
and configure port P31 as an output, as described
above. Then enable transition detection by setting the
2-Wire-Interfaced, 2.5V to 5.5V, 20-Port or
28-Port LED Display Driver and I/O Expander
Table 7. Configuration Register Format
Table 9. Global Current Control (I Data Bit D6) Format
16
Table 8. Shutdown Control (S Data Bit D0) Format
Table 10. Transition Detection Control (M-Data Bit D7) Format
Configuration Register
controlled by one setting in the Global Current
individually controlled by the settings in the
Normal Operation
Current054 through Current1FE registers
______________________________________________________________________________________
Constant-current limits for all digits are
Constant-current limit for each digit is
FUNCTION
FUNCTION
FUNCTION
Shutdown
Disabled
Enabled
Individual Segment
register, 0x02
FUNCTION
Global
ADDRESS CODE
ADDRESS CODE
ADDRESS CODE
(HEX)
(HEX)
(HEX)
0x04
0x04
0x04
0x04
0x04
CODE (HEX)
ADDRESS
D7
D7
D7
M
M
M
0
1
0x04
0x04
D6
D6
D6
I
I
I
I
I
M bit in the configuration register (Table 10). Whenever
the configuration register is written with the M bit set,
the MAX6956 updates an internal 7-bit snapshot regis-
ter, which holds the comparison copy of the logic states
of ports P24 through P30. The update action occurs
regardless of the previous state of the M bit, so that it is
not necessary to clear the M bit and then set it again to
update the snapshot register.
When the configuration register is written with the M bit
set, transition detection is enabled and remains
enabled until either the configuration register is written
D7
M
M
D5
D5
D5
X
X
X
X
X
D6
0
1
REGISTER DATA
REGISTER DATA
REGISTER DATA
D4
D4
D4
X
X
X
X
X
D5
X
X
REGISTER DATA
D4
D3
D3
D3
X
X
X
X
X
X
X
D3
X
X
D2
D2
D2
X
X
X
X
X
D2
X
X
D1
D1
D1
X
X
X
X
X
D1
X
X
D0
D0
D0
S
0
1
S
S
D0
S
S