FDS_6533_6534_004
71M6533/71M6534 Data Sheet
3 Application Information
3.1 Connection of Sensors (CT, Resistive Shunt)
Figure 30 through Figure 32 show how resistive dividers, current transformers, Rogowski coils and resis-
tive shunts are connected to the voltage and current inputs of the 71M6533/71M6534.
VA = Vin * Rout/(Rout + Rin)
VA
Rin
Vin
Rout
Figure 30: Resistive Voltage Divider
Iin
Iout
IIN
IOUT
IA
InP
VDIFF
VOUT
Vout
R
R
V3P3A
InN
V3P3
1/N
1/N
Filter
Figure 31: CT with Single Ended (Left) and Differential Input (Right) Connection
Vout = dIin /dt
Iin
Iin
1/N
IA
IA
R
Vout
Vout
R
VC
V3P3
V3P3
Figure 32: Resistive Shunt (Left), Rogowski Sensor (Right)
3.2 Distinction between 71M6533/71M6534 and 71M6533H/71M6534H Parts
The 71M6533H/71M6534H parts go through an additional process of characterization during production
which makes them suitable to high-accuracy applications.
The first process, applied to both the 71M6533/71M6534 and the 71M6533H/71M6534H, is the trimming
of the reference voltage to the target value of 1.195V.
The second process, which is applied only to the 71M6533H/71M6534H, is the characterization of the
reference voltage over temperature. The coefficients for the reference voltage are stored in trim fuses
(I/O RAM registers TRIMBGA, TRIMBGB, TRIMM[2:0]. The MPU can read these trim fuses and calculate
the correction coefficients PPM1 and PPMC2 per the formulae given in Section 5.4.15 VREF. See Section
3.5 Temperature Compensation for additional details.
The fuse TRIMBGB is non-zero for the 71M6533H/71M6534H part and zero for the 71M6533/71M6533 part.
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