Datasheet

© 2009 Microchip Technology Inc. Preliminary DS39937B-page 157
PIC24F04KA201 FAMILY
21.0 COMPARATOR VOLTAGE
REFERENCE
21.1 Configuring the Comparator
Voltage Reference
The comparator voltage reference module is controlled
through the CVRCON register (Register 21-1). 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 CV
REF 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.
FIGURE 21-1: COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
Note: This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive
reference source. For more information
on the Comparator Voltage Reference,
refer to the “PIC24F Family Reference
Manual”, Section 20. “Comparator
Voltage Reference Module”
(DS39709).
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