Microchip Technology AC164139 Data Sheet

 2010 Microchip Technology Inc.

DS39969B-page 325

The 10-bit A/D Converter has the following key
features:
• Successive Approximation (SAR) conversion
• Conversion speeds of up to 500 ksps
• 24 analog input pins (PIC24FJXXXDAX10 

devices) and 16 analog input pins 
(PIC24FJXXXDAX06 devices)

• External voltage reference input pins
• Internal band gap reference inputs
• Automatic Channel Scan mode
• Selectable conversion trigger source
• 32-word conversion result buffer
• Selectable Buffer Fill modes
• Four result alignment options 
• Operation during CPU Sleep and Idle modes
On all PIC24FJ256DA210 family devices, the 10-bit
A/D Converter has 24 analog input pins, designated
AN0 through AN23. In addition, there are two analog
input pins for external voltage reference connections
(V

REF

+ and V

REF

-). These voltage reference inputs

may be shared with other analog input pins.

A block diagram of the A/D Converter is shown in
Figure 23-1.
To perform an A/D conversion:
1.

Configure the A/D module:
a) Configure the port pins as analog inputs

and/or select band gap reference inputs
(ANCFG registers).

b) Select the voltage reference source to

match the 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 the conversion results are

presented in the buffer (AD1CON1<9:8>).

f)

Select the interrupt rate (AD1CON2<6:2>).

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.

This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive reference
source. For more information, refer to the
“PIC24F Family Reference Manual”,
Section 17. “10-Bit A/D Converter”
(DS39705). The information in this data
sheet supersedes the information in the
FRM.