Datasheet

© 2007 Microchip Technology Inc. DS39599G-page 105
PIC18F2220/2320/4220/4320
FIGURE 10-7: BLOCK DIAGRAM OF
RB2:RB0 PINS
FIGURE 10-8: BLOCK DIAGRAM OF
RB4 PIN
FIGURE 10-9: BLOCK DIAGRAM OF RB3/CCP2 PIN
Data Latch
RBPU
(2)
P
V
DD
Data Bus
WR LATB
WR TRISB
RD TRISB
RD PORTB
Weak
Pull-up
INTx
I/O pin
(1)
Schmitt Trigger
Buffer
TRIS Latch
RD LATB
or PORTB
Note 1: I/O pins have diode protection to VDD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS
bit(s) and clear the RBPU
bit (INTCON2<7>).
To A/D Converter
Analog Input Mode
TTL
Input
Buffer
QD
CK
QD
CK
EN
QD
EN
Data Latch
From RB7:RB5
RBPU
(2)
P
V
DD
I/O pin
(1)
QD
CK
QD
CK
QD
EN
QD
EN
Data Bus
WR LATB
WR TRISB
Set RBIF
TRIS Latch
RD TRISB
RD PORTB
Weak
Pull-up
RD PORTB
Latch
TTL
Input
Buffer
Q3
Q1
RD LATB
or PORTB
Note 1: I/O pins have diode protection to V
DD and VSS.
2: To enable weak pull-ups, set the appropriate TRIS bit(s)
and clear the RBPU
bit (INTCON2<7>).
To A/D Converter
Port/CCP2 Select
Data Bus
WR LATB
WR TRISB
Data Latch
TRIS Latch
RD TRISC
CCP2 Data Out
0
1
P
N
V
DD
VSS
RD PORTB
CCP2 Input
RB3 pin
(1)
or PORTB
RD LATC
Schmitt
Trigger
Note 1: I/O pins have diode protection to V
DD and VSS.
VDD
Weak
Pull-up
P
RBPU
TTL Input
Buffer
Analog Input Mode
Analog Input Mode
To A/D Converter
QD
CK
EN
QD
EN
QD
CK