Maxim Integrated 78M6610+PSU Hardware Design Guidelines - Manual (Page 7)

AN_6610_107 78M6610+PSU Hardware Design Guidelines
Rev. 0 7
3 Alternate Configuration
Voltage and current sensors can alternatively be located right at the AC inlet in front of the EMI filters if
using a current transformer (CT). In this configuration, the measurement device is powered using the
same auxiliary winding from the standby channel, but with a high impedance path between
78M6610+PSU circuitry and AC mains.
I Load
I Secondary
AIN
AIP
750
V
3P3A
750
100n
100n
1000p
1000p
RBurden
CT 78M6610+PSU
10K
10K
AVP
AVN
750
100n
100n
1000p
1000p
750
INLET
LOAD
1M 1M
1M 1M
V
3P3
V
3P3
Neutral
(or Line)
Line
(or Neutral)
Figure 3: Pseudo-Isolated Configuration Example
It is highly recommended to use high-tolerance resistors in the voltage divider to minimize measurement
error caused by divider ratio mis-matching.