ade7566 Analog Devices, Inc., ade7566 Datasheet - Page 45

• Manufacturer Part Number: ade7566
• Description: Single-phase Energy Measurement Ic With 8052 Mcu, Rtc, And Lcd Driver
• Manufacturer: Analog Devices, Inc.

The ADE7569 has a built-in digital integrator to recover the
current signal from the di/dt sensor. The digital integrator on
the current channel is switched off by default when the ADE7569
is powered up. Setting the INTE bit in the MODE1 register (0x0B)
turns on the integrator. Figure 46 to Figure 49 show the
magnitude and phase response of the digital integrator.
Figure 47. Combined Phase Response of the Digital Integrator and
Figure 46. Combined Gain Response of the Digital Integrator and
–88.0
–88.5
–89.0
–89.5
–90.0
–90.5
–10
–20
–30
–40
–50
10
0
100
10
Phase Compensator
Phase Compensator
2
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQ
1000
10
3
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Note that the integrator has a−20 dB/dec attenuation and an
approximately −90° phase shift. When combined with a di/dt
sensor, the resulting magnitude and phase response should be a
flat gain over the frequency band of interest. The di/dt sensor
has a 20 dB/dec gain associated with it. It also generates
significant high frequency noise. Therefore, a more effective
antialiasing filter is needed to avoid noise due to aliasing (see
the Antialiasing Filter section).
When the digital integrator is switched off, the ADE7569 can be
used directly with a conventional current sensor such as a current
transformer (CT) or with a low resistance current shunt.
Figure 49. Combined Phase Response of the Digital Integrator and
Figure 48. Combined Gain Response of the Digital Integrator and
–89.70
–89.75
–89.80
–89.85
–89.90
–89.95
–90.00
–90.05
–1.0
–1.5
–2.0
–2.5
–3.0
–3.5
–4.0
–4.5
–5.0
–5.5
–6.0
40
40
45
Phase Compensator (40 Hz to 70 Hz)
Phase Compensator (40 Hz to 70 Hz)
45
50
50
FREQUENCY (Hz)
FREQUENCY (Hz)
55
55
ADE7566/ADE7569
60
60
65
65
70
70