ADE7763ARSZ Analog Devices Inc, ADE7763ARSZ Datasheet - Page 40

• Manufacturer Part Number: ADE7763ARSZ
• Description: IC ENERGY METERING 1PHASE 20SSOP
• Manufacturer: Analog Devices Inc

Specifications of ADE7763ARSZ

• Input Impedance: 390 KOhm
• Measurement Error: 0.1%
• Voltage - I/o High: 2.4V
• Voltage - I/o Low: 0.8V
• Current - Supply: 3mA
• Voltage - Supply: 4.75 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SSOP (0.200", 5.30mm Width)
• Meter Type: Single Phase
• Ic Function: Single-Phase Active And Apparent Energy Metering IC
• Supply Voltage Range: 4.75V To 5.25V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: SSOP
• No. Of Pins: 20
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-ADE7763ZEB - BOARD EVALUATION FOR ADE7763
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

ADE7763
Phase Calibration
The PHCAL register is provided to remove small phase errors.
The ADE7763 compensates for phase error by inserting a small
time delay or advance on the voltage channel input. Phase leads
up to 1.84° and phase lags up to 0.72° at 50 Hz can be corrected.
The error is determined by measuring the active energy at I
two power factors, PF = 1 and PF = 0.5 inductive.
Some CTs may introduce large phase errors that are beyond the
range of the phase calibration register. In this case, coarse phase
compensation has to be done externally with an analog filter.
The phase error can be obtained from either CF or LAENERGY
measurements:
If watt gain and offset calibration have been performed, there
should be 0% error in CF at unity power factor, and then
The phase error is
The relationship between phase error and the PHCAL phase
correction register is
The expression for PHCAL can be simplified using the
assumption that at small x
The delay introduced in the voltage channel by PHCAL is
The delay associated with the PHCAL register is a time delay if
PHCAL − 0x0D is positive, but represents a time advance if this
quantity is negative. There is no time delay if PHCAL = 0x0D.
The phase correction is in the opposite direction of the
phase error.
Error =
Error = % ERROR
Phase Error (°) = −Arcsin
PHCAL = INT
Arcsin( x ) ≈ x
Delay = ( PHCAL − 0x0D) × 8/ CLKIN
Phase Correction (°) = − ( PHCAL − 0x0D)
LAENERGY
⎛
⎜
⎝
Phase
CF(IB,PF = 0.5)
LAENERGY
IB
,
Error
PF
=
⎛
⎜
⎜
⎝
0
/100
5 .
Error
( )
−
°
3
×
LAENERGY
IB
(
PERIOD
⎞
⎟
⎟
⎠
expected
360
°
)
2
⎞
⎟
⎠
×
IB
+
(
PERIOD
expected
0x0D
360
)
°
2
B
and
(52)
(53)
(54)
(55)
(56)
(57)
Rev. B | Page 40 of 56
Calibrating Phase Using a Reference Meter Example
A power factor of 0.5 inductive can be assumed if the pulse
output rate of the reference meter is half of its PF = 1 rate.
Then, the percent error between CF and the pulse output of
the reference meter can be used to perform the preceding
calculations.
For this example:
CF %ERROR at PF = 0.5 Inductive: % ERROR
PERIOD Register Reading:
Then PHCAL is 11 using Equations 57 through 59:
PHCAL can be expressed as follows:
Note that PHCAL is a signed, twos complement register.
Setting the PHCAL register to 11 provides a phase correction
of 0.08° to correct the phase lead:
Error = 0.215%/100 = 0.00215
Phase Error (°) = −Arcsin
PHCAL = INT
PHCAL =
INT
Phase Correction (°) = −
Phase Correction (°) = −
⎛
⎜
⎜
⎝
Figure 75. Calibrating Phase Using a Reference Meter
−
Arcsin
CALCULATE PHCAL. SEE EQUATION 55.
WRITE PHCAL VALUE TO THE PHCAL
SET I
MEASURE THE % ERROR BETWEEN
REFERENCE METER OUTPUT
⎛
⎜ ⎜
⎝
⎛
⎜
⎝
TEST
THE CF OUTPUT AND THE
−
%
REGISTER: ADDR. 0x10
. 0
ERROR
= I
07
b
, V
°
TEST
×
3
(
(
11
PHCAL
8959
⎛
⎜ ⎜
⎝
360
×
. 0
= V
−
100
00215
°
NOM
0x0D
⎞
⎟
⎠
3
⎞
⎟ ⎟
⎠
+ 0x0D = −2 + 13 = 11
, PF = 0.5
PERIOD = 8959
×
−
)
⎞
⎟ ⎟
⎠
PERIOD
0x0D
×
=
8960
2
360
−
CF(IB,PF = 0.5)
π
. 0
)
×
°
07
=
PERIOD
⎞
⎟
⎟
⎠
°
. 0
+ 0x0D (58)
360
08
= 0.215%
°
°