PIC16F628-20P Datasheet, PDF (58/170 Pages) Microchip Technology – FLASH-Based 8-Bit CMOS Microcontroller

PIC16F62X
9.5 Comparator Outputs
The comparator outputs are read through the CMCON
register. These bits are read only. The comparator
outputs may also be directly output to the RA3 and RA4
I/O pins. When the CM<2:0> = 110, multiplexors in the
output path of the RA3 and RA4/T0CK1 pins will switch
and the output of each pin will be the unsynchronized
output of the comparator. The uncertainty of each of the
comparators is related to the input offset voltage and
the response time given in the specifications. Figure 9-
3 shows the comparator output block diagram.
The TRISA bits will still function as an output enable/
disable for the RA3 and RA4/T0CK1 pins while in this
mode.
Note 1: When reading the PORT register, all pins
configured as analog inputs will read as a
‘0’. Pins configured as digital inputs will
convert an analog input according to the
Schmitt Trigger input specification.
2: Analog levels on any pin that is defined as
a digital input may cause the input buffer
to consume more current than is
specified.
FIGURE 9-3:
COMPARATOR OUTPUT BLOCK DIAGRAM
CnINV
To RA3 or RA4/T0CK1 pin
To Data Bus
CMCON<7:6>
RD CMCON
Q
D
EN
Set CMIF bit
From other Comparator
Q
D
EN
Q1
CL
RESET
CnVOUT
DS40300C-page 56
Preliminary
 2003 Microchip Technology Inc.