Datasheet

Table Of Contents
2002 Microchip Technology Inc. Preliminary DS40044A-page 37
PIC16F627A/628A/648A
FIGURE 5-8: BLOCK DIAGRAM OF
RB0/INT PIN
FIGURE 5-9: BLOCK DIAGRAM OF
RB1/RX/DT PIN
Data Bus
WR PORTB
WR TRISB
RD PORTB
Data Latch
TRIS Latch
RB0/INT
INT
Q
D
CK
EN
QD
EN
RD TRISB
RBPU
P
V
DD
VDD
VSS
Q
Q
D
CK
Q
Weak Pull-up
Schmitt
TTL
Input
Buffer
Trigger
Data Latch
TRIS Latch
RD TRISB
Q
D
Q
CK
Q
D
Q
CK
1
0
WR PORTB
WR TRISB
Schmitt
Trigger
Peripheral OE
(1)
Data Bus
SPEN
USART Data Output
USART Receive Input
RBPU
VDD
P
EN
QD
VDD
VSS
Note 1: Peripheral OE (output enable) is only active if
peripheral select is active.
RD PORTB
RX/DT
RB1/
TTL
Input
Buffer
Weak
Pull-up