CC2430
Peripherals : ADC
13.10 ADC
13.10.1 ADC Introduction
The ADC supports up to 12-bit analog-to-
digital conversion. The ADC includes an
analog multiplexer with up to eight individually
configurable channels, reference voltage
generator and conversion results written to
memory through DMA. Several modes of
operation are available.
•
•
Eight individual input channels, single-
ended or differential
Reference voltage selectable as internal,
external single ended, external differential
or AVDD_SOC.
Interrupt request generation
DMA triggers at end of conversions
Temperature sensor input
•
•
•
•
The main features of the ADC are as follows:
Battery measurement capability
•
Selectable decimation rates which also
sets the resolution (7 to 12 bits).
AIN0
AIN7
Sigma-delta
modulator
Decimation
filter
input
mux
VDD/3
TMP_SENSOR
Int 1.25V
AIN7
ref
mux
AVDD
Clock generation and
control
AIN6-AIN7
Figure 26: ADC block diagram.
13.10.2 ADC Operation
This section describes the general setup and
operation of the ADC and describes the usage
of the ADC control and status registers
accessed by the CPU.
13.10.2.1 ADC Core
The ADC includes an ADC capable of
converting an analog input into a digital
representation with up to 12 bits resolution.
The ADC uses a selectable positive reference
voltage.
13.10.2.2 ADC Inputs
supply can be applied to these pins, nor a
supply larger than VDD (unregulated power). It
is the difference between the pairs that are
converted in differential mode.
The signals on the P0 port pins can be used
as ADC inputs. In the following these port pin
will be referred to as the AIN0-AIN7 pins. The
input pins AIN0-AIN7 are connected to the
ADC. The ADC can be set up to automatically
perform a sequence of conversions and
optionally perform an extra conversion from
any channel when the sequence is completed.
In addition to the input pins AIN0-AIN7, the
output of an on-chip temperature sensor can
be selected as an input to the ADC for
temperature measurements.
It is possible to configure the inputs as single-
ended or differential inputs. In the case where
differential inputs are selected, the differential
inputs consist of the input pairs AIN0-1, AIN2-
3, AIN4-5 and AIN6-7. Note that no negative
CC2430 Data Sheet (rev. 2.1) SWRS036F
Page 128 of 211
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