MAXQ3181 Maxim, MAXQ3181 Datasheet - Page 43

• Manufacturer Part Number: MAXQ3181
• Description: The MAXQ3181 is a dedicated electricity measurement front-end that collects and calculates polyphase voltage, current, active power and energy, and many other metering parameters of a polyphase load
• Manufacturer: Maxim

This register contains the value by which the raw voltage value in each phase (A.VRMS, B.VRMS, and C.VRMS) is
multiplied before being presented to the virtual RMS voltage registers (V.A, V.B, and V.C).
To determine the value of VOLT_CC, a voltage value for the least significant bit (VOLT_LSB) of the V.X registers
must be selected. Typical values might range from 1mV to 1nV. To avoid significant conversion loss, VOLT_LSB
should be chosen such that VOLT_CC is >1000. Once VOLT_LSB is determined, calculate VOLT_CC from the fol-
lowing equation:
This register contains the value by which the raw current value in each phase (A.IRMS, B.IRMS, C.IRMS, and
N.IRMS) is multiplied before being presented to the virtual RMS current registers (I.A, I.B, I.C, and I.N). To determine
the value of AMP_CC, a current value for the least significant bit (AMP_LSB) of the I.X registers must be selected.
Typical values might range from 1nA to 10μA. To avoid significant conversion loss, AMP_LSB should be chosen
such that AMP_CC is >1000. Once determined, calculate AMP_CC from the following equation:
Bit:
Name:
Reset:
Bit:
Name:
Reset:
Bit:
Name:
Reset:
Bit:
Name:
Reset
Low-Power, Active Energy, Polyphase AFE
______________________________________________________________________________________
15
15
7
7
14
14
6
6
VOLT CC
Voltage Units Conversion Coefficient (VOLT_CC) (0x014)
AMP CC
13
Voltage Units Conversion Coefficient High Byte
13
Current Units Conversion Coefficient High Byte
Voltage Units Conversion Coefficient Low Byte
Current Units Conversion Coefficient Low Byte
5
Current Units Conversion Coefficient (AMP_CC) (0x016)
5
_
_
Virtual Register Conversion Coefficients
=
=
2
2
12
12
24
24
4
4
×
×
VOLT LSB
AMP LSB
0x00
0x01
0x00
0x01
I
V
FS
FS
_
_
11
11
3
3
10
10
2
2
9
1
9
1
8
0
8
0
43