PIC16F627A Datasheet, PDF (34/168 Pages) Microchip Technology – FLASH-Based 8-Bit CMOS Microcontrollers

PIC16F627A/628A/648A
FIGURE 5-2:
BLOCK DIAGRAM OF
RA2/VREF PIN
Data
Bus
D
Q
VDD
WR
PORTA
CK Q
Data Latch
WR
TRISA
D
Q
CK Q
TRIS Latch
Analog
Input Mode
(CMCON Reg.)
RA2 Pin
VSS
RD
TRISA
Schmitt Trigger
Input Buffer
Q
D
EN
RD PORTA
To Comparator
VROE
VREF
FIGURE 5-3:
BLOCK DIAGRAM OF THE RA3/AN3 PIN
Data
Bus
WR
PORTA
WR
TRISA
D
Q
CK Q
Data Latch
D
Q
CK Q
TRIS Latch
Comparator Mode = 110 (CMCON Reg.)
Comparator Output
1
0
Analog
Input Mode
(CMCON Reg.)
RD
TRISA
Schmitt Trigger
Input Buffer
Q
D
EN
RD PORTA
To Comparator
VDD
RA3 Pin
VSS
DS40044A-page 32
Preliminary
 2002 Microchip Technology Inc.