Datasheet

 2007-2019 Microchip Technology Inc. DS30009905F-page 227
PIC24FJ256GA110 FAMILY
21.0 10-BIT HIGH-SPEED A/D
CONVERTER
The 10-bit A/D Converter has the following key
features:
• Successive Approximation (SAR) Conversion
• Conversion Speeds of Up to 500 ksps
• 16 Analog Input Pins
• External Voltage Reference Input pins
• Internal Band Gap Reference Inputs
• Automatic Channel Scan mode
• Selectable Conversion Trigger Source
• 16-Word Conversion Result Buffer
• Selectable Buffer Fill modes
• Four Result Alignment Options
• Operation during CPU Sleep and Idle modes
On all PIC24FJ256GA110 family devices, the 10-bit
A/D Converter has 16 analog input pins, designated
AN0 through AN15. In addition, there are two analog
input pins for external voltage reference connections
(V
REF+ and VREF-). These voltage reference inputs
may be shared with other analog input pins.
A block diagram of the A/D Converter is shown in
Figure 21-1.
To perform an A/D conversion:
1. Configure the A/D module:
a) Configure port pins as analog inputs
and/or select the band gap reference input
(AD1PCFGL[15:0] and AD1PCFGH[1:0]).
b) Select the voltage reference source to
match expected range on analog inputs
(AD1CON2[15:13]).
c) Select the analog conversion clock to match
the desired data rate with the processor
clock (AD1CON3[7:0]).
d) Select the appropriate sample/conversion
sequence (AD1CON1[7:5] and
AD1CON3[12:8]).
e) Select how conversion results are
presented in the buffer (AD1CON1[9:8]).
f) Select the interrupt rate (AD1CON2[5:2]).
g) Turn on the A/D module (AD1CON1[15]).
2. Configure the A/D interrupt (if required):
a) Clear the AD1IF bit.
b) Select the A/D interrupt priority.
Note: This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive refer-
ence source. For more information,
refer to “10-Bit A/D Converter”
(www.microchip.com/DS39705) in the
“dsPIC33/PIC24 Family Reference Man-
ual”. The information in this data sheet
supersedes the information in the FRM.