User Manual

1.5.6 Using D/I/O of the 7522A (D)
(valid for 7522A(D)/7524(D)/7527(D))
Inductive load or
Conductive load
Current Limit Resistor
Load current <= 125mA
Ext. GND
Ext. 24V
Dry contact or TTL/CMOS
or (3.5V to 30V D/I)
16
1
5
TXD3
+
TXD
3
-
18
19
20
21
22
1
7
23
RXD3
+
GND
DI3
75
22A
DI2
DI1
DI0
RXD3
-
PW
R
DO0
DO1
DO2
DO3
24
2
5
26
27
2
8
X507
GND
+
VS
D2
-
D2+
14
1
3
12
11
10
9
8
7
6
5
INIT
*
t
RXD1
TXD1
GND
RTS1
CTS1
D1
-
DI
+
DI
4
3
2
D
O
1
+5V
UA
74HCT08
1
2
3
R2
10K
R1
10K
D/I
TO_CPU
7522A
19~22
D/I Block Diagram
D/O Block Diagram
DO0
DO1
DO2
DO3
PWR
U1
ULN2003A
SOIC 16
1
2
3
4
5
6
28
27
26
25
24
7
8
9
10
11
12
13
14
15
16
B0
B1
B2
B3
B4
B5
COM
C5
C4
C3
C2
C1
C0
B6
E
C6
7521/2/2A/3/4/7 Series Hardware User’s Manual, Ver. 1.5 Sep/2002, 7Mh-001-15 -----37