71M6511 Maxim, 71M6511 Datasheet - Page 77

• Manufacturer Part Number: 71M6511
• Description: The 71M6511 and 71M6511H are highly integrated SoCs with an MPU core, RTC, flash, and LCD driver
• Manufacturer: Maxim

APPLICATION INFORMATION
Connection of Sensors (CT, Resistive Shunt, Rogowski Coil)
Figure 27 and Figure 28 show how resistive dividers, current transformers, restive shunts, and Rogowski coils are connected
to the voltage and current inputs of the 71M6511.
Distinction between 71M6511 and 71M6511H Parts
71M6511H parts go through a process of trimming and characterization during production that make them suitable to high-
accuracy applications.
The first process applied to the 71M6511H is the trimming of the reference voltage, which is guaranteed to have accuracy over
temperature of better that ±10PPM/°C.
The second process applied to the 71M6511H is the characterization of the reference voltage over temperature. The
coefficients for the reference voltage are stored in so-called trim fuses (I/O RAM registers TRIMBGA, TRIMBGB, TRIMM[2:0].
The MPU program can read these trim fuses and calculate the correction coefficients PPM1 and PPM2 per the formulae given
in the Performance Specifications section (VREF, VBIAS). See the Temperature Compensation section for details.
The fuse TRIMBGB is non-zero for the 71M6511H part and zero for the 71M6511 part.
Trim fuse information is not available for non-H parts. Thus, the standard are to be applied. These settings are:
Page: 77 of 98
Figure 27: Resistive Voltage Divider (left), Current
V
•
•
in
The analog input pins of the 71M6511 are designed for sensors with low source impedance. RC filters with resistance
values higher than those implemented in the Teridian Demo Boards should be avoided.
A Maxim Integrated Products Brand
PPMC = TC1 * 22.46 = –149
PPMC2 = TC2 * 1150.1 = –392
VA = Vin * R
R
in
out
/(R
out
Figure 28: Resistive Shunt (left), Rogowski Coil (right)
R
+ R
out
© 2005–2010 Teridian Semiconductor Corporation
in
)
VA
(right)
Single-Phase Energy Meter IC
71M6511/71M6511H
V
Vout = dI
DATA SHEET
out
R
in
/dt
I
1/N
in
Vout = dI
V
out
in
R
/dt
IA
V
C
V3P3
NOVEMBER 2010
Transformer
V2.7