PIC12F635/PIC16F636/639
TABLE 1-3:
PIC16F639 PINOUT DESCRIPTIONS
Input
Type
Output
Type
Name
Function
Description
LCCOM
LCCOM
LCX
AN
AN
AN
AN
TTL
—
—
—
—
—
Common reference for analog inputs.
125 kHz analog X channel input.
125 kHz analog Y channel input.
125 kHz analog Z channel input.
LCX
LCY
LCY
LCZ
LCZ
RA0/C1IN+/ICSPDAT/ULPWU
RA0
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
—
Comparator1 input – positive.
CMOS Serial Programming Data IO.
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
—
—
—
Comparator1 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 Comparator1 output.
TTL
General purpose input. Individually controlled
interrupt-on-change.
RA3/MCLR/VPP
—
Master Clear Reset. Pull-up enabled when configured as MCLR.
MCLR
VPP
ST
HV
—
—
Programming voltage.
RA4
TTL
CMOS General purpose I/O. Individually controlled interrupt-on-change.
Individually enabled pull-up/pull-down.
RA4/T1G/OSC2/CLKOUT
ST
—
Timer1 gate.
T1G
OSC2
CLKOUT
RA5
—
—
XTAL XTAL connection.
CMOS TOSC 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/4 reference clock.
RC0/C2IN+
TTL
AN
CMOS General purpose I/O.
C2IN+
RC1
—
Comparator1 input – positive.
TTL
AN
CMOS General purpose I/O.
RC1/C2IN-/CS
C2IN-
—
—
Comparator1 input – negative.
TTL
Chip select input for SPI communication with internal pull-up
resistor.
CS
RC2
SCLK
ALERT
TTL
TTL
—
CMOS General purpose I/O.
RC2/SCLK/ALERT
—
Digital clock input for SPI communication.
Output with internal pull-up resistor for AFE error signal.
= Direct
OD
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
OD = Open Drain
TTL = TTL compatible input
DS41232D-page 14
© 2007 Microchip Technology Inc.