PIC16F639 Microchip Technology Inc., PIC16F639 Datasheet - Page 56

• Manufacturer Part Number: PIC16F639
• Description: 8/14-pin Flash-based, 8-bit Cmos Microcontrollers With Nanowatt Technology
• Manufacturer: Microchip Technology Inc.

PIC12F635/PIC16F636/639
4.2.4.4
Figure 4-4 shows the diagram for this pin. The RA3 pin
is configurable to function as one of the following:
• a general purpose input
• as Master Clear Reset with weak pull-up
• a high-voltage detect for Program mode entry
FIGURE 4-4:
DS41232D-page 54
RA3/MCLR/V
Interrupt-on-
BLOCK DIAGRAM OF RA3
change
PP
Data Bus
PORTA
IOCA
TRISA
WR
RD
RD
RD
IOCA
D
CK
Q
Q
Program
Mode
V
SS
Reset
MCLRE
HV Detect
WURE
Sleep
RD PORTA
MCLRE
Q
Q
MCLRE
EN
EN
D
D
V
DD
Weak
Q1
V
SS
Input
© 2007 Microchip Technology Inc.
pin