MCP23017/MCP23S17
1.1
Pin Descriptions
TABLE 1-1:
PINOUT DESCRIPTION
PDIP/
SOIC/
SSOP
Pin
Name
Pin
Type
QFN
Function
GPB0
GPB1
GPB2
GPB3
GPB4
GPB5
GPB6
GPB7
1
2
3
4
5
6
7
8
25
26
27
28
1
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
2
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
3
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
4
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
VDD
9
5
6
P
P
I
Power
VSS
10
11
12
13
14
15
16
17
18
19
20
21
Ground
NC/CS
SCL/SCK
SDA/SI
NC/SO
A0
7
NC (MCP23017), Chip Select (MCP23S17)
Serial clock input
8
I
9
I/O Serial data I/O (MCP23017), Serial data input (MCP23S17)
10
11
12
13
14
15
16
17
O
I
NC (MCP23017), Serial data out (MCP23S17)
Hardware address pin. Must be externally biased.
A1
I
Hardware address pin. Must be externally biased.
A2
I
Hardware address pin. Must be externally biased.
RESET
INTB
INTA
GPA0
I
Hardware reset. Must be externally biased.
O
O
Interrupt output for PORTB. Can be configured as active-high, active-low or open-drain.
Interrupt output for PORTA. Can be configured as active-high, active-low or open-drain.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA1
GPA2
GPA3
GPA4
GPA5
GPA6
GPA7
22
23
24
25
26
27
28
18
19
20
21
22
23
24
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
DS21952B-page 4
© 2007 Microchip Technology Inc.