ADE7569ASTZF16 Analog Devices Inc, ADE7569ASTZF16 Datasheet - Page 55

• Manufacturer Part Number: ADE7569ASTZF16
• Description: IC ENERGY METER MCU 16K 64LQFP
• Manufacturer: Analog Devices Inc

Specifications of ADE7569ASTZF16

• Applications: Energy Measurement
• Core Processor: 8052
• Program Memory Type: FLASH (16 kB)
• Controller Series: ADE75xx
• Ram Size: 512 x 8
• Interface: I²C, SPI, UART
• Number Of I /o: 20
• Voltage - Supply: 3.135 V ~ 3.465 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Ic Function: Single Phase Energy Measurement IC
• Supply Voltage Range: 3.13V To 3.46V, 2.4V To 3.7V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: LQFP
• No. Of Pins: 64
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Fault with Inactive Input Greater Than Active Input
If the difference between I
active input (that is, being used for billing), becomes greater
than 6.25% of I
ACCMODE register (Address 0x0F) is cleared, the FAULTSIGN
flag (Bit 5) in the Interrupt Status 1 SFR (MIRQSTL, Address
0xDC) is set. The I
Again, a time constant of about 3 seconds is associated with this
swap. I
greater than I
order—becomes greater than 6.25% of I
FAULTSIGN bit (Bit 6) of the ACCMODE register (Address 0x0F)
is set, the FAULTSIGN flag (Bit 5) in the Interrupt Status 1 SFR
(MIRQSTL, Address 0xDC) is set as soon as I
of I
and I
Calibration Concerns
Typically, when a meter is calibrated, the voltage and current
circuits are separated, as shown in Figure 49. Current passes
through only the phase circuit or the neutral circuit. Figure 49
shows current being passed through the phase circuit. This is
the preferred option because the ADE7116/ADE7156/
ADE7166/ADE7169 start billing on the I
The phase circuit CT is connected to I
Because the current sensors are not perfectly matched, it is
important to match current inputs. The ADE7116/
ADE7156/ADE7166/ADE7169 provide a gain calibration
register for I
signed, twos complement register that provides a gain
resolution of 0.0244%/LSB.
For calibration, a first measurement should be done on I
setting the SEL_I_CH bits to 0b01 in the CALMODE register
(Address 0x3D). This measurement should be compared to the
measurement on I
SEL_I_CH bits to 0b10 in the CALMODE register (Address 0x3D).
The gain error between these two measurements can be evaluated
using the following equation:
The two channels, I
−Error(%)/(1 + Error (%)) × 2
(Address 0x1C). This matching adjustment is valid for all
energy measurements made by the ADE7116/ADE7156/
ADE7166/ADE7169, including active power, reactive power
(ADE7169 only), apparent power, and I
PB
. This threshold eliminates potential chatter between I
PB
Error
.
PA
does not become the active channel again until I
( )
%
PB
PB
, IBGAIN (Address 0x1C). IBGAIN is a 12-bit,
=
PB
and the difference between I
Measuremen
, and the FAULTSIGN bit (Bit 6) of the
PB
PB
PA
. Measuring I
analog input becomes the active input.
and I
PB
Measuremen
PB
, the inactive input, and I
I t
, can then be matched by writing
( )
12
B
to the IBGAIN register
PB
−
can be forced by setting the
Measuremen
PA
I t
( )
rms
PB
in the diagram.
PA
A
. However, if the
.
input on power-up.
PA
PA
ADE7116/ADE7156/ADE7166/ADE7169/ADE7566/ADE7569
and I
I t
is within 6.25%
( )
A
PB
PA
—in this
, the
PA
PA
by
PA
is
Rev. B | Page 55 of 152
(2)
CURRENT
di/dt CURRENT SENSOR AND DIGITAL
INTEGRATOR FOR THE ADE7169/ADE7569
A di/dt sensor, a feature available for the AD7169/ADE7569 but
not for the ADE7116/ADE7156/ADE7166/ADE7169, detects
changes in the magnetic field caused by ac currents. Figure 50
shows the principle of a di/dt current sensor.
The flux density of a magnetic field induced by a current is
directly proportional to the magnitude of the current. The
changes in the magnetic flux density passing through a conductor
loop generate an electromotive force (EMF) between the two
ends of the loop. The EMF is a voltage signal that is proportional
to the di/dt of the current. The voltage output from the di/dt
current sensor is determined by the mutual inductance between
the current-carrying conductor and the di/dt sensor. The current
signal needs to be recovered from the di/dt signal before it can
be used. An integrator is, therefore, necessary to restore the
signal to its original form.
Figure 49. Fault Conditions for Inactive Input Greater Than Active Input
TEST
I
PB
240V rms
Figure 50. Principle of a di/dt Current Sensor
V
AGND
R
0
A
R
F
MAGNETIC FIELD CREATED BY CURRENT
(DIRECTLY PROPORTIONAL TO CURRENT)
CT
CT
R
R
C
B
B
F
+ EMF (ELECTROMOTIVE FORCE)
– INDUCED BY CHANGES IN
0V
V
MAGNETIC FLUX DENSITY (di/dt)
A
R
C
R
R
F
T
F
F
V
V
P
N
C
C
F
F
I
I
I
PA
PB
N