78M6610+LMU Data Sheet
Phase Compensation
Phase compensation registers are used to compensate for phase errors or time delays between the
voltage input source and respective current source that are introduced by the off-chip sensor circuit. The
user configurable registers are signed fixed point numbers with the binary point to the left of bit 21. Values
are in units of high rate (4kHz) sample delays so each integer unit of delay is 250µs with a total possible
delay of ±4 samples (roughly ±20° at 60Hz).
Register
Description
PHASECOMP1
PHASECOMP3
Phase (delay) compensation for S1 input current
Phase (delay) compensation for S3 input current
Example:
To compensate a phase error of 277.77µs (or 6° at 60Hz) introduced by a current transformer (CT) it is
necessary to enter the following:
푃ℎ푎푠푒 퐸푟푟표푟
푃ℎ푎푠푒 퐶표푚푝푒푛푠푎푡푖표푛 =
1
푆푎푚푝푙푒 푅푎푡푒
277퐸−6
푃ℎ푎푠푒 퐶표푚푝푒푛푠푎푡푖표푛 =
= 1.111
1
4000
The value to be entered in the phase compensation register is therefore:
푃퐶표푚푝 = 1.111 ∗ 221 = 2330169 = 0x238E39
19
Rev 0
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
