Datasheet

 2002-2013 Microchip Technology Inc. DS30487D-page 53
PIC16F87/88
FIGURE 5-2: BLOCK DIAGRAM OF RA3/AN3/VREF+/C1OUT PIN
FIGURE 5-3: BLOCK DIAGRAM OF RA2/AN2/CV
REF/VREF- PIN
Data
Bus
QD
Q
CK
N
WR
PORTA
WR
TRISA
Data Latch
TRIS Latch
RD TRISA
RD PORTA
V
SS
RA3 pin
QD
Q
CK
DQ
EN
To A/D Module Channel Input (PIC16F88 only)
Comparator 1 Output
Comparator Mode = 110
VDD
Analog
Input Mode
To A/D Module Channel VREF+ Input (PIC16F88 only)
P
VDD
To Comparator
VSS
Input Buffer
TTL
Data
Bus
QD
Q
CK
P
N
WR
PORTA
WR
TRISA
Data Latch
TRIS Latch
RD TRISA
RD PORTA
Analog
V
SS
VDD
RA2 pin
QD
Q
CK
DQ
EN
To Comparator
TTL
Input Buffer
Input Mode
VDD
To A/D Module Channel Input (PIC16F88 only)
CVROE
CV
REF
To A/D Module VREF- (PIC16F88 only)