PIC12F635/PIC16F636/639
TABLE 1-2:
PIC16F636 PINOUT DESCRIPTIONS
Input
Type
Output
Type
Name
Function
Description
RA0/C1IN+/ICSPDAT/ULPWU
RA0
TTL
—
General purpose I/O. Individually controlled
interrupt-on-change. Individually enabled pull-up/pull-down.
Selectable Ultra Low-Power Wake-up pin.
C1IN+
ICSPDAT
ULPWU
RA1
AN
TTL
AN
—
Comparator 1 input – positive.
CMOS Serial programming data I/O.
Ultra Low-Power Wake-up input.
—
RA1/C1IN-/VREF/ICSPCLK
RA2/T0CKI/INT/C1OUT
TTL
CMOS General purpose I/O. Individually controlled
interrupt-on-change. Individually enabled pull-up/pull-down.
C1IN-
VREF
AN
AN
ST
ST
—
—
—
Comparator 1 input – negative.
External voltage reference
Serial programming clock.
ICSPCLK
RA2
CMOS General purpose I/O. Individually controlled
interrupt-on-change. Individually enabled pull-up/pull-down.
T0CKI
INT
ST
ST
—
—
External clock for Timer0.
External interrupt.
C1OUT
RA3
—
CMOS Comparator 1 output.
RA3/MCLR/VPP
TTL
ST
—
—
—
General purpose input. Individually controlled interrupt-on-change.
MCLR
VPP
Master Clear Reset. Pull-up enabled when configured as MCLR.
Programming voltage.
HV
TTL
RA4/T1G/OSC2/CLKOUT
RA4
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up/pull-down.
T1G
OSC2
CLKOUT
RA5
ST
—
—
Timer1 gate.
XTAL XTAL connection.
—
CMOS TOSC/4 reference clock.
RA5/T1CKI/OSC1/CLKIN
TTL
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up/pull-down.
T1CKI
OSC1
CLKIN
RC0
ST
XTAL
ST
—
—
—
Timer1 clock.
XTAL connection.
TOSC reference clock.
RC0/C2IN+
RC1/C2IN-
TTL
AN
CMOS General purpose I/O.
C2IN+
RC1
—
Comparator 1 input – positive.
TTL
AN
CMOS General purpose I/O.
C2IN-
RC2
—
Comparator 1 input – negative.
RC2
TTL
TTL
TTL
—
CMOS General purpose I/O.
CMOS General purpose I/O.
CMOS General purpose I/O.
CMOS Comparator 2 output.
CMOS General purpose I/O.
RC3
RC3
RC4/C2OUT
RC4
C2OUT
RC5
RC5
VDD
VSS
TTL
D
VDD
—
—
Power supply for microcontroller.
Ground reference for microcontroller.
VSS
D
Legend: AN = Analog input or output
HV = High Voltage
CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels
XTAL = Crystal
D = Direct
TTL = TTL compatible input
© 2007 Microchip Technology Inc.
DS41232D-page 13