CS5461 datasheet(16/46 Pages) CIRRUS

16 / 46 page

CS5461

DS546PP2

Note that until the CS5461 is calibrated (see Cali-

bration) the accuracy of the CS5461 (with respect

to a reference line-voltage and line-current level on

the power mains) is not guaranteed to within

0.1%. But the linearity of any given sample of

CS5461, before calibration, will be within ±0.1%

of reading over the ranges specified, with respect to

the input voltage levels required to cause full-scale

readings in the Irms/Vrms Registers. Table 1 de-

scribes linearity + variation specs after the comple-

tion of each successive computation cycle.

The accuracy of the internal calculations can often

be improved by selecting a value for the Cy-

cle-Count Register that will cause the time duration

of one computation cycle to be equal (or very close

to) a whole-number of power-line cycles (and N

must be greater than or equal to 4000). For exam-

ple, with the cycle count set to 4200, the ±0.1% of

reading linearity range for measurement of a 60 Hz

sinusoidal current-sense voltage signal can be in-

creased beyond the range of 0.2% - 70.7%. The lin-

earity range can be increased because (4200

samples / 60 Hz) is a whole number of cycles (70).

CS5461 数据表(PDF) 16 Page - Cirrus Logic