Cirrus Logic CS5464 - Manual (Page 33)

CS5464
DS682F3 33
8.3 Page 1 Registers
8.3.1 DC Offset for Current (I1
OFF
, I2
OFF
) and Voltage (V1
OFF
, V2
OFF
)
Address: 0 (I1
OFF
), 2 (V1
OFF
), 7 (I2
OFF
), 9 (V2
OFF
)
Default = 0
DC offset registers I1
OFF
& V1
OFF
( I2
OFF
& V2
OFF
) are initialized to zero on reset. During DC offset calibration,
selected registers are written with the inverse of the DC offset measured. The application program can also write
the DC offset register values. These are two's complement values in the range of -1.0
 value  1.0, with the
binary point to the right of the MSB.
8.3.2 Gain for Current (I1
GAIN
, I2
GAIN
) and Voltage (V1
GAIN
, V2
GAIN
)
Address: 1 (I1
GAIN
), 3 (V1
GAIN
), 8 (I2
GAIN
), 10 (V2
GAIN
)
Default = 1.0
Gain registers I1
GAIN
& V1
GAIN
( I2
GAIN
& V2
GAIN
) are initialized to 1.0 on reset. During AC or DC gain calibration,
selected register are written with the multiplicative inverse of the gain measured. These are unsigned fixed-point
values in the range of 0
 value  4.0, with the binary point to the right of the second MSB.
8.3.3 Power Offset (P1
OFF
, P2
OFF
)
Address: 4 (P1
OFF
), 11 (P2
OFF
)
Default = 0
Power offset P1
OFF
(P2
OFF
) is added to instantaneous power and averaged over a low-rate interval to yield
P1
AVG
(P2
AVG
) register results. It can be used to reduce systematic energy errors. These are two's complement
values in the range of -1.0
 value  1.0, with the binary point to the right of the MSB.
8.3.4 AC Offset for Current (I1
ACOFF
, I2
ACOFF
) and Voltage (V1
ACOFF
, V2
ACOFF
)
Address: 5 (I1
ACOFF
), 6 (V1
ACOFF
), 12 (I2
ACOFF
), 13 (V2
ACOFF
)
Default = 0
AC offset registers I1
ACOFF
& V1
ACOFF
( V
ACOFF
& V2
ACOFF
) are initialized to zero on reset. These are added to
the RMS results before being stored to the RMS result registers. They can be used to reduce systematic errors
in the RMS results. These are two's complement values in the range of -1.0
 value  1.0, with the binary point
to the right of the MSB.
MSB LSB
-(2
0
) 2
-1
2
-2
2
-3
2
-4
2
-5
2
-6
2
-7 ..... 2
-17
2
-18
2
-19
2
-20
2
-21
2
-22
2
-23
MSB LSB
2
1
2
0
2
-1
2
-2
2
-3
2
-4
2
-5
2
-6 ..... 2
-16
2
-17
2
-18
2
-19
2
-20
2
-21
2
-22
MSB LSB
-(2
0
) 2
-1
2
-2
2
-3
2
-4
2
-5
2
-6
2
-7 ..... 2
-17
2
-18
2
-19
2
-20
2
-21
2
-22
2
-23
MSB LSB
-(2 0 ) 2 -1 2 -2 2 -3 2 -4 2 -5 2 -6 2 -7 ..... 2 -17 2 -18 2 -19 2 -20 2 -21 2 -22 2 -23