Datasheet

dsPIC30F6011/6012/6013/6014
DS70117F-page 142 © 2006 Microchip Technology Inc.
19.9 Module Power-down Modes
The module has 2 internal Power modes.
When the ADON bit is ‘1’, the module is in Active mode;
it is fully powered and functional.
When ADON is ‘0’, the module is in Off mode. The dig-
ital and analog portions of the circuit are disabled for
maximum current savings.
In order to return to the Active mode from Off mode, the
user must wait for the ADC circuitry to stabilize.
19.10 ADC Operation During CPU Sleep
and Idle Modes
19.10.1 ADC OPERATION DURING CPU
SLEEP MODE
When the device enters Sleep mode, all clock sources
to the module are shutdown and stay at logic ‘0’.
If Sleep occurs in the middle of a conversion, the con-
version is aborted. The converter will not continue with
a partially completed conversion on exit from Sleep
mode.
Register contents are not affected by the device
entering or leaving Sleep mode.
The ADC module can operate during Sleep mode if the
ADC clock source is set to RC (ADRC = 1). When the
RC clock source is selected, the A/D module waits one
instruction cycle before starting the conversion. This
allows the SLEEP instruction to be executed which elim-
inates all digital switching noise from the conversion.
When the conversion is complete, the CONV bit will be
cleared and the result loaded into the ADCBUF register.
If the A/D interrupt is enabled, the device will wake-up
from Sleep. If the A/D interrupt is not enabled, the ADC
module will then be turned off, although the ADON bit
will remain set.
19.10.2 A/D OPERATION DURING CPU IDLE
MODE
The ADSIDL bit selects if the module will stop on Idle or
continue on Idle. If ADSIDL = 0, the module will con-
tinue operation on assertion of Idle mode. If ADSIDL =
1, the module will stop on Idle.
19.11 Effects of a Reset
A device Reset forces all registers to their Reset state.
This forces the ADC module to be turned off, and any
conversion and sampling sequence is aborted. The val-
ues that are in the ADCBUF registers are not modified.
The A/D Result register will contain unknown data after
a Power-on Reset.
19.12 Output Formats
The ADC result is 12 bits wide. The data buffer RAM is
also 12 bits wide. The 12-bit data can be read in one of
four different formats. The FORM<1:0> bits select the
format. Each of the output formats translates to a 16-bit
result on the data bus.
FIGURE 19-5: ADC OUTPUT DATA FORMATS
RAM Contents: d11 d10 d09 d08 d07 d06 d05 d04 d03 d02 d01 d00
Read to Bus:
Signed Fractional d11 d10d09d08d07d06d05d04d03d02d01d000000
Fractional d11d10d09d08d07d06d05d04d03d02d01d000000
Signed Integer d11 d11 d11 d11 d11 d10 d09 d08 d07 d06 d05 d04 d03 d02 d01 d00
Integer 0000d11d10d09d08d07d06d05d04d03d02d01d00