Datasheet

71M6543F/71M6543G Data Sheet
v2 87
4.4 System Using Current Transformers
Figure 32 shows a polyphase system using four current transformers to support optional Neutral current
sensing for anti-tamper purposes. The Neutral current sensing CT can be omitted if Neutral current
sensing is not required. The system is referenced to Neutral (i.e., the Neutral rail is tied to V3P3A and
V3P3SYS).
MPU
RTC
TIMERS
IADC2
VADC8 (VA)
IADC4
VADC9 (VB)
XIN
XOUT
RX
TX
TX
RX
COM0...5
V3P3A V3P3SYS
VBAT
VBAT_RTC
IADC6
VADC10 (VC)
SEG
GNDA GNDD
SEG/DIO
DIO
ICE
A
B
C
NEUTRAL
LOAD
8888.8888
PULSES,
DIO
IR
AMR
POWER FAULT
COMPARATOR
MODUL-
ATOR
SERIAL PORTS
OSCILLATOR/
PLL
MUX and ADC
LCD DRIVER
DIO, PULSES
COMPUTE
ENGINE
FLASH
MEMORY
RAM
32 kHz
REGULATOR
Current Transformers
POWER SUPPLY
71M6543F/
71M6543G
TEMPERATURE
SENSOR
VREF
IADC0
BATTERY
PWR MODE
CONTROL
WAKE-UP
NEUTRAL
I
2
C or µWire
EEPROM
9/17/2010
IADC3
IADC5
IADC7
IADC1
RTC
BATTERY
V3P3D
BATTERY
MONITOR
SPI INTERFACE
HOST
LCD DISPLAY
Resistor Dividers
Note: This system is referenced to Neutral
}IA
}IB
}IC
}IN*
*IN = Optional Neutral Current
Figure 32. System Using Current Transformers