Microchip Technology TDGL002 - chipKIT Uno32 Development Board TDGL002 TDGL002 Data Sheet

© 2011 Microchip Technology Inc.

DS61143H-page 127

The CV

REF

 is a 16-tap, resistor ladder network that pro-

vides a selectable reference voltage. Although its pri-
mary 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 illustrated in

. 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 refer-
ence can be provided from either device V

DD

/V

SS

 or an

external voltage reference. The CV

REF

 output is avail-

able 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

Note 1: This data sheet summarizes the features

of the PIC32MX3XX/4XX family of
devices. It is not intended to be a compre-
hensive reference source. Refer to Sec-
tion 20. “Comparator Voltage
Reference (CV

)” (DS61109) of the

“PIC32 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
available on all devices. Refer to

 in

this data sheet for device-specific register
and bit information.

1

6

-to-

1 MUX

CVR3:CVR0

8R

R

CVREN

CVRSS = 0

AV

DD

V

REF

+

CVRSS = 1 

8R

CVRSS = 0

V

REF

-

CVRSS = 1 

R

R

R

R

R

R

16 Steps

CVRR

CV

REF

OUT

AV

SS

CVRCON<CVROE>

CV

REF