Datasheet

MCP23017/MCP23S17
DS21952B-page 4 © 2007 Microchip Technology Inc.
1.1 Pin Descriptions
TABLE 1-1: PINOUT DESCRIPTION
Pin
Name
PDIP/
SOIC/
SSOP
QFN
Pin
Type
Function
GPB0 1 25 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB1 2 26 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB2 3 27 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB3 4 28 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB4 5 1 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB5 6 2 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB6 7 3 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPB7 8 4 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
V
DD
95PPower
V
SS
10 6 P Ground
NC/CS
11 7 I NC (MCP23017), Chip Select (MCP23S17)
SCL/SCK 12 8 I Serial clock input
SDA/SI 13 9 I/O Serial data I/O (MCP23017), Serial data input (MCP23S17)
NC/SO 14 10 O NC (MCP23017), Serial data out (MCP23S17)
A0 15 11 I Hardware address pin. Must be externally biased.
A1 16 12 I Hardware address pin. Must be externally biased.
A2 17 13 I Hardware address pin. Must be externally biased.
RESET
18 14 I Hardware reset. Must be externally biased.
INTB 19 15 O Interrupt output for PORTB. Can be configured as active-high, active-low or open-drain.
INTA 20 16 O Interrupt output for PORTA. Can be configured as active-high, active-low or open-drain.
GPA0 21 17 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA1 22 18 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA2 23 19 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA3 24 20 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA4 25 21 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA5 26 22 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA6 27 23 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.
GPA7 28 24 I/O Bidirectional I/O pin. Can be enabled for interrupt-on-change and/or internal weak pull-up
resistor.