71M6511H-IGT/F Maxim Integrated Products, 71M6511H-IGT/F Datasheet - Page 47
![IC ENERGY METER RESIDENT 64-LQFP](/photos/37/60/376099/lqfp64_sml.jpg)
71M6511H-IGT/F
Manufacturer Part Number
71M6511H-IGT/F
Description
IC ENERGY METER RESIDENT 64-LQFP
Manufacturer
Maxim Integrated Products
Datasheet
1.71M6511H-IGTF.pdf
(98 pages)
Specifications of 71M6511H-IGT/F
Processor Series
6511x
Core
80515
Data Bus Width
8 bit
Program Memory Type
Flash
Program Memory Size
64 KB
Data Ram Size
7 KB
Interface Type
I2C, SSI, UART
Maximum Clock Frequency
5 MHz
Number Of Programmable I/os
12
Number Of Timers
2
Operating Supply Voltage
3 V to 3.6 V
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
Package / Case
LQFP-64
3rd Party Development Tools
PK51, CA51, A51, ULINK2
Development Tools By Supplier
71M6511H-DB
Minimum Operating Temperature
- 40 C
On-chip Adc
22 bit Delta Sigma
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
71M6511H-IGT/F
Manufacturer:
PERICOM
Quantity:
1 200
Company:
Part Number:
71M6511H-IGT/F
Manufacturer:
Maxim Integrated
Quantity:
10 000
FUNCTIONAL DESCRIPTION
Theory of Operation
The energy delivered by a power source into a load can be expressed as:
Assuming phase angles are constant, the following formulae apply:
For a practical meter, not only voltage and current amplitudes, but also phase angles and harmonic content may change
constantly. Thus, simple RMS measurements are inherently inaccurate. A modern solid-state electricity meter IC such as the
71M6511/6511H functions by emulating the integral operation above, i.e. it processes current and voltage samples through an
ADC at a constant frequency. As long as the ADC resolution is high enough and the sample frequency is beyond the harmonic
range of interest, the current and voltage samples, multiplied with the time period of sampling will yield an accurate quantity for
the momentary energy. Summing up the momentary energy quantities over time will result in accumulated energy.
Figure 12 shows the shapes of V(t), I(t), the momentary and the accumulated energy, resulting from 50 samples of the voltage
and current signals over a period of 20ms. The application of 240VAC and 100A results in an accumulation of 480Ws over the
20ms period, as indicated by the Accumulated Power curve.
The described sampling method works reliably, even in the presence of dynamic phase shift and harmonic distortion.
System Timing Summary
Page: 47 of 98
A Maxim Integrated Products Brand
P = Real Energy [Wh] = V * A * cos φ* t
Q = Reactive Energy [VARh] = V * A * sin φ * t
S = Apparent Energy [VAh] =
-100
-200
-300
-400
-500
500
400
300
200
100
0
Figure 12: Voltage. Current, Momentary and Accumulated Energy
0
Current [A]
Voltage [V]
Energy per Interval [Ws]
Accumulated Energy [Ws]
© 2005–2010 Teridian Semiconductor Corporation
P +
2
5
E
Q
=
2
∫
0
t
V
) (
t
10
t I
Single-Phase Energy Meter IC
) (
dt
71M6511/71M6511H
DATA SHEET
15
time [ms]
20
NOVEMBER 2010
V2.7