cs5467 Cirrus Logic, Inc., cs5467 Datasheet - Page 15

• Manufacturer Part Number: cs5467
• Description: Four-channel Power / Energy Ic
• Manufacturer: Cirrus Logic, Inc.

4.4 DC Offset and Gain Correction
The system and chip inherently have gain and offset er-
rors which can be removed using the gain and offset
registers. (See
40). Each measurement channel has its own registers.
For every channel, the output of the IIR filter is added to
the offset register and multiplied by the gain register.
4.5 High-pass Filters
Optional high-pass filters (HPF in Figures
move any DC from the selected signal paths. Subse-
quently, DC will also be removed from power, and all
low-rate results. (see Figures 5).
Each energy channel has a current and voltage path. If
an HPF is enabled in only one path, a phase-matching
filter (PMF) is applied to the other path which matches
the amplitude and phase delay of the HPF in the band
DS714F1
Section 9. System Calibration
3
and 4) re-
on page
of interest, but passes DC. For more information, see
6.5 High-pass Filters
plexers drive the I1 , V1 , I2 , and V2 result registers.
4.6 Low-Rate Calculations
Low-rate results are derived from sample-rate results
integrated over N samples, where N is the value stored
in the Cycle Count register. The low-rate interval is the
sample interval multiplied by N .
4.7 RMS Results
The root mean square ( RMS in
are performed on N instantaneous voltage and current
samples, using the formula:
I RMS
on page 20. The HPF filter multi-
=
-------------------- -
n
N 1
∑
=
–
N
0
Figure
I n
2
5) calculations
CS5467
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