Datasheet
dsPIC30F6010A/6015
DS70150E-page 144 © 2011 Microchip Technology Inc.
The configuration guidelines give the required setup
values for the conversion speeds above 500 ksps,
since they require external VREF pins usage and there
are some differences in the configuration procedure.
Configuration details that are not critical to the
conversion speed have been omitted.
Figure 20-2 depicts the recommended circuit for the
conversion rates above 500 ksps.
FIGURE 20-2: A/D CONVERTER VOLTAGE REFERENCE SCHEMATIC
20.7.1 1 Msps CONFIGURATION
GUIDELINE
The configuration for 1 Msps operation is dependent on
whether a single input pin is to be sampled or whether
multiple pins will be sampled.
20.7.1.1 Single Analog Input
For conversions at 1 Msps for a single analog input, at
least two sample and hold channels must be enabled.
The analog input multiplexer must be configured so
that the same input pin is connected to both sample
and hold channels. The A/D converts the value held on
one S/H channel, while the second S/H channel
acquires a new input sample.
20.7.1.2 Multiple Analog Inputs
The A/D converter can also be used to sample multiple
analog inputs using multiple sample and hold channels.
In this case, the total 1 Msps conversion rate is divided
among the different input signals. For example, four
inputs can be sampled at a rate of 250 ksps for each
signal or two inputs could be sampled at a rate of
500 ksps for each signal. Sequential sampling must be
used in this configuration to allow adequate sampling
time on each input.
V
DD
V
SS
V
SS
V
DD
V
DD
V
REF
-
V
REF
+
AV
DD
AV
SS
V
SS
V
DD
V
SS
dsPIC30F6010A
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
V
DD
R2
10
C2
0.1
μ
F
C1
0.01
μ
F
R1
10
C8
1
μ
F
V
DD
C7
0.1
μ
F
V
DD
C6
0.01
μ
F
V
DD
C5
1
μ
F
V
DD
C4
0.1
μ
F
V
DD
C3
0.01
μ
F