71M6521DE Datasheet, PDF (59/101 Pages) Teridian Semiconductor Corporation – Energy Meter IC

71M6521DE/71M6521FE
Energy Meter IC
DATASHEET
JANUARY 2008
APPLICATION INFORMATION
Connection of Sensors (CT, Resistive Shunt)
Figure 28 and Figure 29 show how resistive dividers, current transformers, and restive shunts are connected to the voltage and
current inputs of the 71M6521DE/FE.
VA = Vin * R_out/(R_out + R_in)
VA
V_in
R_in
R_out
core
Vout = R * I_out = R * I_in/N
I_in
I_out
IA ^Iin
R
V_out
V3P3
1/N
Filter
I_out
Figure 28: Resistive Voltage Divider (Left), Current Transformer (Right)
Vout = R * I_in
I_in
IA
R
V_out
V3P3
I_in
Figure 29: Resistive Shunt
v1.0
© 2005-2008 TERIDIAN Semiconductor Corporation
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