MA160014 Microchip Technology, MA160014 Datasheet - Page 337

• Manufacturer Part Number: MA160014
• Description: MOD PLUG-IN 44PIN PIC18LF45K22
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of MA160014

• Accessory Type: Plug-In Module (PIM) - PIC18LF45K10
• Product: Microcontroller Modules
• Data Bus Width: 8 bit
• Core Processor: PIC18LF45K22
• Interface Type: I2C, SPI
• Operating Supply Voltage: 1.8 V to 5.5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PICDEM PIC18 Explorer, DM183032
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

21.0
The Fixed Voltage Reference, or FVR, is a stable
voltage reference, independent of V
2.048V or 4.096V selectable output levels. The output
of the FVR can be configured to supply a reference
voltage to the following:
• ADC input channel
• ADC positive reference
• Comparator positive input
• Digital-to-Analog Converter (DAC)
The FVR can be enabled by setting the FVREN bit of
the VREFCON0 register.
FIGURE 21-1:
 2010 Microchip Technology Inc.
FIXED VOLTAGE REFERENCE
(FVR)
FVRS<1:0>
VOLTAGE REFERENCE BLOCK DIAGRAM
FVREN
FVRST
2
DD
+
_
, with 1.024V,
X
X
X
1.024V Fixed
Reference
1
2
4
Preliminary
21.1
The output of the FVR supplied to the ADC,
Comparators
independent
amplifier can be configured to amplify the 1.024V
reference voltage by 1x, 2x or 4x, to produce the three
possible voltage levels.
The FVRS<1:0> bits of the VREFCON0 register are
used to enable and configure the gain amplifier settings
for the reference supplied to the DAC and Comparator
modules. When the ADC module is configured to use
the FVR output, (FVR BUF2) the reference is buffered
through an additional unity gain amplifier. This buffer is
disabled if the ADC is not configured to use the FVR.
For specific use of the FVR, refer to the specific module
sections:
(ADC)
Converter (DAC) Module”
parator
21.2
When the Fixed Voltage Reference module is enabled, it
requires time for the reference and amplifier circuits to
stabilize. Once the circuits stabilize and are ready for use,
the FVRST bit of the VREFCON0 register will be set. See
Section 27.0 “Electrical Characteristics”
minimum delay requirement.
X
1
PIC18(L)F2X/4XK22
Module”,
Module”.
Independent Gain Amplifiers
FVR Stabilization Period
Section 17.0 “Analog-to-Digital Converter
programmable
and
Section 22.0 “Digital-to-Analog
(To Comparators, DAC)
DAC
(To ADC Module)
FVR BUF2
FVR BUF1
and
is
gain
routed
Section 18.0 “Com-
DS41412D-page 337
amplifier.
through
for the
The
an