71M6531F-IM/F Maxim Integrated Products, 71M6531F-IM/F Datasheet - Page 92

• Manufacturer Part Number: 71M6531F-IM/F
• Description: IC ENERGY METER 256KB 68-QFN
• Manufacturer: Maxim Integrated Products

Specifications of 71M6531F-IM/F

• Mounting Style: SMD/SMT
• Package / Case: QFN-68
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

interrupt. They remain constant throughout each accumulation interval. In this data sheet, the names of
CE transfer variables always end with _X.
The transfer variables can be categorized as:
1. Fundamental energy measurement variables
2. Instantaneous (RMS) values
3. Other measurement parameters
Fundamental Energy Measurement Variables
Table 61
32-bit integers. Accumulated variables such as WSUM are internally scaled so they have at least 2x
margin before overflow when the integration time is one second. Additionally, the hardware will not permit
output values to fold back upon overflow.
based on the specified LSB value.
For example, with VMAX = 600 V and IMAX = 208 A, the LSB for WxSUM_X is 0.08356 µWh.
Instantaneous Measurement Variables
Table 62
selected with FREQSELn bits in the CECONFIG register.
IxSQSUM_X and VxSQSUM are the squared current and voltage samples acquired during the last accumulation
interval. They can be used to calculate RMS voltages and currents. INSQSUM_X can be used for computing
the neutral current.
Data Sheet 71M6531D/F-71M6532D/F
4.3.7
When the MPU receives the XFER_BUSY interrupt, it knows that fresh data is available in the transfer
variables. CE transfer variables are modified during the CE code pass that ends with an XFER_BUSY
WxSUM_X is the Wh value accumulated for element X in the last accumulation interval and can be computed
92
Address
Address
0x8C
0x8A
0x8B
0x85
0x86
0x87
0x8F
0x82
CE
CE
CE Transfer Variables
describes each transfer variable for fundamental energy measurement. All variables are signed
contains various measurement results. The Frequency measurement is computed for the phase
VAR0SUM_X
VAR1SUM_X
VARSUM_X
I0SQSUM_X
W0SUM_X
W1SUM_X
WSUM_X
FREQ_X
Name
Name
© 2005-2010 TERIDIAN Semiconductor Corporation
Table 62: CE Energy Measurement Variables
For EQU[2:0] = 2, this register holds the calculated sum of Wh samples
from each wattmeter element (In_8 is the gain of 1 or 8 configured by
IA_SHUNT or IB_SHUNT).
The sum of Wh samples from each wattmeter element (In_8 is the gain
of 1 or 8 configured by IA_SHUNT or IB_SHUNT).
For EQU[2:0] = 2, this register holds the calculated sum of VARh
samples from each element (In_8 is the gain of 1 or 8 configured by
IA_SHUNT or IB_SHUNT).
The sum of VARh samples from each element (In_8 is the gain 1 or 8
configured by IA_SHUNT or IB_SHUNT).
Fundamental frequency.
The sum of squared current samples from each element.
Table 61: CE Transfer Variables
LSB = 6.6952*10
LSB = 6.6952*10
LSB = 6.6952*10
LSB = 6.6952*10
LSB
≡
2
F
32
S
≈
. 0
587
-13
-13
-13
-13
VMAX IMAX / In_8 Wh.
VMAX IMAX / In_8 Wh.
VMAX IMAX / In_8 VARh.
VMAX IMAX / In_8 VARh.
⋅
10
−
Description
6
Description
Hz
FDS 6531/6532 005
v1.3