Rainbow Electronics 71M6542G - Manual (Page 94)

94 © 2008–2011 Teridian Semiconductor Corporation v1.1
4.4 71M6541D/F Using 71M6x01and Current Shunts
Figure 36 shows a typical connection for one isolated and one non-isolated shunt sensor, using the
71M6x01 Isolated Sensor Interface. This configuration implements a single-phase measurement with
tamper-detection using the second current sensor. This configuration can also be used to create a split
phase meter (e.g., ANSI Form 2S). For best performance, the IAP-IAN current sensor input is configured
for differential mode (i.e., DIFFA_E = 1, I/O RAM 0x210C[4]). The outputs of the 71M6x01 Isolated Sensor
Interface are routed through a pulse transformer, which is connected to the pins IBP-IBN. The IBP-IBN
pins must be configured for remote sensor communication (i.e., RMT_E =1, I/O RAM 0x2709[3]). See
Figure 3 for the AFE configuration corresponding to Figure 36 .
MPU
RTC
TIMERS
IAP
VA
IBP
XIN
XOUT
RX
TX
TX
RX
COM0...5
V3P3A V3P3SYS
VBAT
VBAT_RTC
SEG
GNDA GNDD
SEG/DIO
DIO
ICE
LINE
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
Shunt
POWER SUPPLY
TERIDIAN
71M6541D/F
TEMPERATURE
SENSOR
VREF
BATTERY
PWR MODE
CONTROL
WAKE-UP
NEUTRAL
I 2 C or µWire
EEPROM
IAN
IBN
RTC
BATTERY
V3P3D
BATTERY
MONITOR
SPI INTERFACE HOST
LCD DISPLAY
Resistor Divider
Pulse
Trans-
former
TERIDIAN
71M6xx1
Shunt
LINE
LINE
Note:
This system is referenced to LINE
11/5/2010
Figure 36: 71M6541D/F with 71M6x01 isolated Sensor