Converting readings into measured values

AN3254

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Doc ID 17783 Rev 1

For SYS configuration bits 2 or 3 (no neutral wire) the voltage value should be further

multiplied by 2:

u = u * 2

5.2.2

Other values

The ACR, ACS, and ACT registers hold the information needed for this calculation.

Concatenating ACT[7:0], ACS[7:0], and ACR[7:0] bytes, two 12-bit vectors, defined below,

are obtained:

ACT[7:0], ACS[7:0], ACR[7:0] = Asr[11, 10:0], Art[11, 10:0]

The delay times are calculated with the following formulas:

The phase delays in degrees can be calculated as follows:

time

Asr

Asr 10 0

;

[]

2

11

()

Asr 11

[]

–

1

+

()

8

f

MCLK

---------------

⋅

=

time

Art

Art 10 0

;

[]

2

11

()

Asr 11

[]

–

1

+

()

8

f

MCLK

---------------

⋅

=

Table 6.

MDIV

4.000 MHz

0

8.000 MHz

4.194 MHz

0

8.192 MHz

4.915 MHz

0

9.830 MHz

8.000 MHz

1

8.000 MHz

8.192 MHz

1

8.192 MHz

9.830 MHz

1

9.830 MHz

ϕ°

time

f

line

------------ 360

°

⋅

=