PIC32MX575F256H-80I Datasheet, PDF (149/236 Pages) Microchip Technology – High-Performance, USB, CAN and Ethernet 32-Bit Flash Microcontrollers

PIC32MX5XX/6XX/7XX
26.0 COMPARATOR VOLTAGE
REFERENCE (CVREF)
Note 1: This data sheet summarizes the features
of the PIC32MX5XX/6XX/7XX family of
devices. It is not intended to be a compre-
hensive reference source. To complement
the information in this data sheet, refer to
Section 20. “Comparator Voltage
Reference (CVREF)” (DS61109) in the
“PIC32MX Family Reference Manual”,
which is available from the Microchip web
site (www.microchip.com/PIC32).
2: Some registers and associated bits
described in this section may not be avail-
able on all devices. Refer to Section 4.0
“Memory Organization” in this data
sheet for device-specific register and bit
information.
The CVREF module is a 16-tap, resistor ladder network
that provides a selectable reference voltage. Although
its primary purpose is to provide a reference for the
analog comparators, it also may be used independently
of them.
A block diagram of the module is shown in Figure 26-1.
The resistor ladder is segmented to provide two ranges
of voltage reference values and has a power-down
function to conserve power when the reference is not
being used. The module’s supply reference can be pro-
vided from either device VDD/VSS or an external
voltage reference. The CVREF output is available for
the comparators and typically available for pin output.
The comparator voltage reference has the following
features:
• High and low range selection
• Sixteen output levels available for each range
• Internally connected to comparators to conserve
device pins
• Output can be connected to a pin
FIGURE 26-1:
COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM
VREF+
CVRSS = 1
AVDD
CVRSS = 0
8R
CVREN
R
R
R
R
16 Steps
CVRR
VREF-
AVSS
R
R
R
CVRSS = 1
CVRSS = 0
CVR<3:0>
CVREF
CVREFOUT
CVRCON<CVROE>
8R
 2010 Microchip Technology Inc.
Preliminary
DS61156C-page 149