ADE7752BARW AD [Analog Devices], ADE7752BARW Datasheet - Page 11

• Manufacturer Part Number: ADE7752BARW
• Description: Polyphase Energy Metering IC with Pulsed Output
• Manufacturer: AD [Analog Devices]

Preliminary Technical Data
TERMINOLOGY
Measurement Error
The error associated with the energy measurement made by the
ADE7752B is defined by the following formula:
Error between Channels
The high-pass filter (HPF) in the current channel has a phase
lead response. To offset this phase response and equalize the
phase response between channels, a phase correction network is
placed in the current channel. The phase correction network
ensures a phase match between the current channels and
voltage channels to within ±0.1° over a range of 45 Hz to 65 Hz
and ±0.2° over a range of 40 Hz to 1 kHz (see Figure 25 and
Figure 26).
Power Supply Rejection (PSR)
This quantifies the ADE7752B measurement error as a
percentage of reading when the power supplies are varied.
For the ac PSR measurement, a reading at a nominal supply
(5 V) is taken. A 200 mV rms/100 Hz signal is then introduced
onto the supply and a second reading is obtained under the
same input signal levels. Any error introduced is expressed as a
percentage of reading. See definition for Measurement Error.
For the dc PSR measurement, a reading at nominal supplies
(5 V) is taken. The supply is then varied ±5% and a second
reading is obtained with the same input signal levels. Any error
introduced is again expressed as a percentage of reading.
Percentage
Error
=
⎧
⎨
⎩
Energy
Registered
True
by
ADE
Energy
7762
–
True
Energy
⎫
⎬
⎭
×
100
Rev. PrA | Page 11 of 27
%
ADC Offset Error
This refers to the dc offset associated with the analog inputs to
the ADCs. It means that with the analog inputs connected to
AGND, the ADCs still see an analog input signal offset.
However, because the HPF is always present, the offset is
removed from the current channel and the power calculation is
not affected by this offset.
Gain Error
The gain error of the ADE7752B is defined as the difference
between the measured output frequency (minus the offset) and
the ideal output frequency. The difference is expressed as a
percentage of the ideal frequency. The ideal frequency is
obtained from the ADE7752B transfer function (see the
Transfer Function section).
ADE7752B