MAX7219C/D Maxim, MAX7219C/D Datasheet - Page 9

• Manufacturer Part Number: MAX7219C/D
• Description: Serially Interfaced / 8-Digit LED Display Drivers
• Manufacturer: Maxim

The scan-limit register sets how many digits are dis-
played, from 1 to 8. They are displayed in a multiplexed
manner with a typical display scan rate of 800Hz with 8
digits displayed. If fewer digits are displayed, the scan
rate is 8f
Table 7. Intensity Register Format (Address (Hex) = XA)
Table 8. Scan-Limit Register Format (Address (Hex) = XB)
*See Scan-Limit Register section for application.
Display digit 0 only*
Display digits 0 & 1*
Display digits 0 1 2*
Display digits 0 1 2 3
Display digits 0 1 2 3 4
Display digits 0 1 2 3 4 5
Display digits 0 1 2 3 4 5 6
Display digits 0 1 2 3 4 5 6 7
Serially Interfaced, 8-Digit LED Display Drivers
MAX7219
(min on)
11/32
13/32
15/32
17/32
19/32
21/32
23/32
25/32
27/32
29/32
31/32
1/32
3/32
5/32
7/32
9/32
DUTY CYCLE
OSC
SCAN LIMIT
/N, where N is the number of digits
MAX7221
_______________________________________________________________________________________
(max on)
(min on)
10/16
11/16
12/16
13/16
14/16
15/16
15/16
1/16
2/16
3/16
4/16
5/16
6/16
7/16
8/16
9/16
Scan-Limit Register
D7
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
D7
X
X
X
X
X
X
X
X
D6
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
D6
X
X
X
X
X
X
X
X
D5
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
D5
X
X
X
X
X
X
X
X
D4
scanned. Since the number of scanned digits affects
the display brightness, the scan-limit register should
not be used to blank portions of the display (such as
leading zero suppression). Table 8 lists the scan-limit
register format.
REGISTER DATA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
D4
X
X
X
X
X
X
X
X
D3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
D3
X
X
X
X
X
X
X
X
D2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
D2
0
0
0
0
1
1
1
1
D1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
D1
0
0
1
1
0
0
1
1
D0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
D0
0
1
0
1
0
1
0
1
CODE
HEX
CODE
XA
XB
XC
XD
X0
X1
X2
X3
X4
X5
X6
X7
X8
X9
XE
XF
HEX
X0
X1
X2
X3
X4
X5
X6
X7
9