PIC16F676 Microchip Technology Inc., PIC16F676 Datasheet - Page 41

• Manufacturer Part Number: PIC16F676
• Description: 14-pin, Flash-based 8-bit Cmos Microcontroller
• Manufacturer: Microchip Technology Inc.

© 2007 Microchip Technology Inc.
6.2
There are eight modes of operation for the comparator.
The CMCON register, shown in Register 6-1, is used to
select the mode. Figure 6-2 shows the eight possible
modes. The TRISA register controls the data direction
of the comparator pins for each mode. If the
FIGURE 6-2:
Comparator Reset (POR Default Value - low power)
CM2:CM0 = 000
Comparator without Output
CM2:CM0 = 010
Comparator with Output and Internal Reference
CM2:CM0 = 011
Comparator with Output
CM2:CM0 = 001
A = Analog Input, ports always reads ‘0’
D = Digital Input
CIS = Comparator Input Switch (CMCON<3>)
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
Comparator Configuration
A
A
D
A
A
D
A
D
D
A
A
D
COMPARATOR I/O OPERATING MODES
From CV
REF
Module
Off (Read as '0')
COUT
COUT
COUT
Comparator Off (Lowest power)
CM2:CM0 = 111
Comparator w/o Output and with Internal Reference
CM2:CM0 = 100
Multiplexed Input with Internal Reference and Output
CM2:CM0 = 101
Multiplexed Input with Internal Reference
CM2:CM0 = 110
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
RA1/CIN-
RA0/CIN+
RA2/COUT
Comparator mode is changed, the comparator output
level may not be valid for a specified period of time.
Refer to the specifications in Section 12.0.
Note:
D
D
D
A
D
D
A
A
D
A
A
D
Comparator interrupts should be disabled
during a Comparator mode change. Other-
wise, a false interrupt may occur.
PIC16F630/676
CIS = 0
CIS = 1
CIS = 0
CIS = 1
From CV
From CV
From CV
REF
Module
REF
REF
Off (Read as '0')
COUT
Module
DS40039E-page 39
Module
COUT
COUT