Microchip Technology MA330025-1 Data Sheet

 2009-2012 Microchip Technology Inc.

DS70616G-page 413

The dsPIC33EPXXX(GP/MC/MU)806/810/814 and
PIC24EPXXX(GP/GU)810/814 devices have two ADC
modules, ADC1 and ADC2. The ADC1 module
supports up to 32 analog input channels. The ADC2
module supports up to 16 analog input channels.
On ADC1, the AD12B bit (AD1CON1<10>) allows each
of the ADC modules to be configured by the user as
either a 10-bit, 4 Sample-and-Hold (S&H) ADC (default
configuration) or a 12-bit, 1 S&H ADC. 

The ADC2 module only supports 10-bit operation with
4 S&H.

The 10-bit ADC configuration has the following key
features:
• Successive Approximation (SAR) Conversion
• Conversion Speeds of up to 1.1 Msps
• Up to 32 Analog Input Pins
• External Voltage Reference Input Pins
• Simultaneous Sampling of up to Four Analog 

Input Pins

• Automatic Channel Scan mode
• Selectable Conversion Trigger Source
• Selectable Buffer Fill modes
• Four Result Alignment Options (signed/unsigned, 

fractional/integer)

• Operation during CPU Sleep and Idle modes
The 12-bit ADC configuration supports all the above
features, except:
• In the 12-bit configuration, conversion speeds of 

up to 500 ksps are supported

• There is only one S&H amplifier in the 12-bit 

configuration, so simultaneous sampling of 
multiple channels is not supported.

Depending on the particular device pinout, the ADC
can have up to 32 analog input pins, designated AN0
through AN31. In addition, there are two analog input
pins for external voltage reference connections. These
voltage reference inputs can be shared with other ana-
log input pins. The actual number of analog input pins
and external voltage reference input configuration
depends on the specific device.
A block diagram of the ADC module is shown in

 provides a diagram of the

ADC conversion clock period.

Note 1: This data sheet summarizes the features

of the dsPIC33EPXXX(GP/MC/MU)806/
810/814 and PIC24EPXXX(GP/GU)810/
814 families of devices. It is not intended
to be a comprehensive reference source.
To complement the information in this
data sheet, refer to Section 16. “Analog-
to-Digital Converter (ADC)” (DS70621)
of the “dsPIC33E/PIC24E Family Refer-
ence Manual”, which is available from the
Microchip web site (

www.microchip.com

).

2: Some registers and associated bits

described in this section may not be
available on all devices. Refer to

 in

this data sheet for device-specific register
and bit information.

The ADC1 module needs to be disabled
before modifying the AD12B bit.