36.6.2.9 Accumulation

The result from multiple consecutive conversions can be accumulated. The number of samples to be accumulated is specified by the Sample Number field in the Average Control register (AVGCTRL.SAMPLENUM). When accumulating more than 16 samples, the result will be too large to match the 16-bit RESULT register size. To avoid overflow, the result is right shifted automatically to fit within the available register size. The number of automatic right shifts is specified in the table below.

Note: To perform the accumulation of two or more samples, the Conversion Result Resolution field in the Control C register (CTRLC.RESSEL) must be set depending on the final result precision. For resolutions strictly higher than 12 bits, RESSEL must be set to 16 bits.

Table 36-1. Accumulation
Number of Accumulated Samples	AVGCTRL. SAMPLENUM	Number of Automatic Right Shifts	Final Result Precision	Automatic Division Factor
1	0x0	0	12 bits	0
2	0x1	0	13 bits	0
4	0x2	0	14 bits	0
8	0x3	0	15 bits	0
16	0x4	0	16 bits	0
32	0x5	1	16 bits	2
64	0x6	2	16 bits	4
128	0x7	3	16 bits	8
256	0x8	4	16 bits	16
512	0x9	5	16 bits	32
1024	0xA	6	16 bits	64
Reserved	0xB –0xF		12 bits	0