71m6543h-igtr/f Maxim Integrated Products, Inc., 71m6543h-igtr/f Datasheet - Page 11

• Manufacturer Part Number: 71m6543h-igtr/f
• Description: Energy Meter Ic
• Manufacturer: Maxim Integrated Products, Inc.

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In a typical application, the 32-bit compute engine (CE) of the 71M6543F/H sequentially processes the
samples from the voltage inputs on analog input pins and performs calculations to measure active energy
(Wh) and reactive energy (VARh), as well as A
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The Teridian 71M6543F/H single-chip energy meter integrates all primary functional blocks required to
implement a solid-state electricity meter. Included on the chip are:
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In order to implement a polyphase meter with or without neutral current sensing, one resistive shunt
current sensor may be connected directly (non-isolated) to the 71M6543F/H device, while up to three
additional current shunts are isolated using a companion 71M6xx3 isolated sensor IC. An inexpensive,
small size pulse transformer is used to electrically isolate the 71M6xx3 remote sensor from the
71M6543F/H. The 71M6543F/H performs digital communications bi-directionally with the 71M6xx3 and
also provides power to the 71M6xx3 through the isolating pulse transformer. Isolated (remote) shunt
current sensors are connected to the differential input of the 71M6xx3. The 71M6543F/H may also be
used with Current Transformers; in this case the 71M6xx3 isolated sensors are not required. Included on
the 71M6xx3 companion isolator chip are:
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are then accessed by the MPU, processed further and output using the peripheral devices available to the
MPU.
In addition to advanced measurement functions, the real time clock (RTC) function allows the 71M6543F/H
to record time of use (TOU) metering information for multi-rate applications and to time-stamp tamper or
other events. An automatic RTC temperature compensation circuit operates in all power states including
when the MPU is halted, and continues to compensate using back-up battery power during power outages.
Measurements can be displayed on 3.3 V LCDs commonly used in low-temperature environments. The
integrated charge pump and temperature sensor can be used by the MPU to enhance 3.3 V LCD
performance at cold temperatures. The on-chip charge pump may also drive 5 V LCDs. Flexible mapping of
LCD display segments facilitates the integration of existing custom LCDs. Design trade-off between the
v1.0
An analog front-end (AFE) featuring a 22-bit second-order sigma-delta ADC
An independent 32-bit digital computation engine (CE) to implement DSP functions
An 8051-compatible microprocessor (MPU) which executes one instruction per clock cycle (80515)
A precision voltage reference (VREF)
A temperature sensor for digital temperature compensation of:
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LCD Driver
RAM and Flash memory
A real time clock (RTC)
A variety of I/O pins
A power failure interrupt
A zero-crossing interrupt
Selectable current sensor interfaces for locally-connected sensors as well as isolated sensors (i.e.,
using the 71M6xx3 companion IC with a shunt resistor sensor)
Resistive Shunt and Current Transformers are supported
Digital isolation communications interface
An analog front-end (AFE) featuring a 22-bit second-order sigma-delta ADC
A precision voltage reference (VREF)
A temperature sensor (for current-sensing digital temperature compensation)
A fully differential shunt resistor sensor input
A pre-amplifier to optimize shunt current sensor performance
Isolated power circuitry obtains dc power from pulses sent by the 71M6543F/H
Hardware Description
Hardware Overview
Metrology (MPU)
Automatic RTC in all power states
MPU assisted RTC compensation
© 2008–2011 Teridian Semiconductor Corporation
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h, and V
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h for four-quadrant metering. These measurements
71M6543F/H Data Sheet
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