MAX7221EWG Maxim Integrated Products, MAX7221EWG Datasheet - Page 9

• Manufacturer Part Number: MAX7221EWG
• Description: LED Drivers
• Manufacturer: Maxim Integrated Products

Specifications of MAX7221EWG

• Number Of Digits: 8
• Number Of Segments: 64
• Low Level Output Current: 320 mA
• High Level Output Current: - 45 mA
• Operating Supply Voltage: 4 V to 5.5 V
• Maximum Supply Current: 330 mA
• Maximum Power Dissipation: 941 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOIC-24 Wide
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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) = 0xXA)
Table 8. Scan-Limit Register Format (Address (Hex) = 0xXB)
* 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
0xXC
0xXD
0xXA
0xXB
0xXE
0xX0
0xX1
0xX2
0xX3
0xX4
0xX5
0xX6
0xX7
0xX8
0xX9
0xXF
HEX
CODE
0xX0
0xX1
0xX2
0xX3
0xX4
0xX5
0xX6
0xX7
HEX
9