SAM3X8E Atmel Corporation, SAM3X8E Datasheet - Page 1339

• Manufacturer Part Number: SAM3X8E
• Manufacturer: Atmel Corporation

43.6.11
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
Buffer Structure
A minimal Tracking Time is necessary for the ADC to guarantee the best converted final value
between two channel selections. This time has to be programmed through the TRACKTIM bit
field in the Mode Register, ADC_MR.
When the gain, offset or differential input parameters of the analog cell change between two
channels, the analog cell may need a specific settling time before starting the tracking phase. In
that case, the controller automatically waits during the settling time defined in the
Register”. Obviously, if the ANACH option is not set, this time is unused.
Warning: No input buffer amplifier to isolate the source is included in the ADC. This must be
taken into consideration to program a precise value in the TRACKTIM field. See the product
ADC Characteristics section.
The PDC read channel is triggered each time a new data is stored in ADC_LCDR register. The
same structure of data is repeatedly stored in ADC_LCDR register each time a trigger event
occurs. Depending on user mode of operation (ADC_MR, ADC_CHSR, ADC_SEQR1,
ADC_SEQR2) the structure differs. Each data transferred to PDC buffer, carried on a half-word
(16-bit), consists of last converted data right aligned and when TAG is set in ADC_EMR register,
the 4 most significant bits are carrying the channel number thus allowing an easier post-process-
ing in the PDC buffer or better checking the PDC buffer integrity.
SAM3X/A
SAM3X/A
“ADC Mode
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