Datasheet

 2005-2012 Microchip Technology Inc. DS39747F-page 193
PIC24FJ128GA010 FAMILY
23.0 COMPARATOR VOLTAGE
REFERENCE
23.1 Configuring the Comparator
Voltage Reference
The voltage reference module is controlled through the
CVRCON register (Register 23-1). The comparator
voltage reference provides two ranges of output
voltage, each with 16 distinct levels. The range to be
used is selected by the CVRR bit (CVRCON<5>). The
primary difference between the ranges is the size of the
steps selected by the CVREF Selection bits
(CVR<3:0>), with one range offering finer resolution.
The comparator reference supply voltage can come
from either V
DD and VSS, or the external VREF+ and
V
REF-. The voltage source is selected by the CVRSS
bit (CVRCON<4>).
The settling time of the comparator voltage reference
must be considered when changing the CV
REF
output.
CVRR: Comparator V
REF Range Selection bit 1 = 0
to 0.625 CV
RSRC, with CVRSRC/24 step size.
0 = 0.25 CV
RSRC to 0.72 CVRSRC, with CVRSRC/32
step size
FIGURE 23-1: COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
Note: This data sheet summarizes features of
PIC24F group of devices and is not
intended to be a comprehensive reference
source. Refer to Section 20. “Comparator
Voltage Reference Module” (DS39709)
in the “PIC24F Family Reference Manual”
for more information.
16-to-1 MUX
CVR<3:0>
8R
R
CVREN
CVRSS = 0
AV
DD
VREF+
CVRSS = 1
8R
CVRSS = 0
V
REF-
CVRSS = 1
R
R
R
R
R
R
16 Steps
CVRR
CVREF
AVSS