DSPIC30F MICROCHIP [Microchip Technology], DSPIC30F Datasheet - Page 147

• Manufacturer Part Number: DSPIC30F
• Description: General Purpose and Sensor Families High-Performance Digital Signal Controllers
• Manufacturer: MICROCHIP [Microchip Technology]

19.0
The 12-bit Analog-to-Digital converter (A/D) allows
conversion of an analog input signal to a 12-bit digital
number. This module is based on a Successive
Approximation Register (SAR) architecture and pro-
vides a maximum sampling rate of 100 ksps. The A/D
module has up to 16 analog inputs which are multi-
plexed into a sample and hold amplifier. The output of
the sample and hold is the input into the converter
which generates the result. The analog reference volt-
age is software selectable to either the device supply
voltage (AV
(V
feature of being able to operate while the device is in
Sleep mode with RC oscillator selection.
FIGURE 19-1:
 2004 Microchip Technology Inc.
Note: This data sheet summarizes features of this group
of dsPIC30F devices and is not intended to be a complete
reference source. For more information on the CPU,
peripherals, register descriptions and general device
functionality, refer to the dsPIC30F Family Reference
Manual (DS70046).
REF
+/V
AN13
AN15
AN10
AN11
AN12
AN14
AN0
AN1
AN2
AN3
AN4
AN5
AN6
AN7
AN8
AN9
12-BIT ANALOG-TO-DIGITAL
CONVERTER (A/D) MODULE
REF
V
V
DD
-) pin. The A/D converter has a unique
REF
REF
/AV
+
-
SS
) or the voltage level on the
12-BIT A/D FUNCTIONAL BLOCK DIAGRAM
CH0G
CH0R
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Preliminary
S/H
Sample
CH0
The A/D module has six 16-bit registers:
• A/D Control Register 1 (ADCON1)
• A/D Control Register 2 (ADCON2)
• A/D Control Register 3 (ADCON3)
• A/D Input Select Register (ADCHS)
• A/D Port Configuration Register (ADPCFG)
• A/D Input Scan Selection Register (ADCSSL)
The ADCON1, ADCON2 and ADCON3 registers con-
trol the operation of the A/D module. The ADCHS reg-
ister selects the input channels to be converted. The
ADPCFG register configures the port pins as analog
inputs or as digital I/O. The ADCSSL register selects
inputs for scanning.
The block diagram of the 12-bit A/D module is shown in
Figure 19-1.
Note:
The SSRC<2:0>, ASAM, SMPI<3:0>,
BUFM and ALTS bits, as well as the
ADCON3 and ADCSSL registers, must
not be written to while ADON = 1. This
would lead to indeterminate results.
12-bit SAR
Switches
DAC
Input
16-word, 12-bit
Sample/Sequence
Dual Port
Buffer
Comparator
Conversion Logic
Control
dsPIC30F
Input Mux
Control
AV
DD
DS70083G-page 145
AV
SS