MCP3909RD-3PH3 Microchip Technology, MCP3909RD-3PH3 Datasheet - Page 68

• Manufacturer Part Number: MCP3909RD-3PH3
• Description: REF DESIGN FOR MCP3909 W/18F2520
• Manufacturer: Microchip Technology

Specifications of MCP3909RD-3PH3

• Main Purpose: Power Management, Energy/Power Meter
• Utilized Ic / Part: MCP3909, PIC18F2520, PIC18F4550
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

MCP3909 3-Phase Energy Meter Reference Design
6.9
DS51643B-page 64
METER DESIGN FRAME
This frame contains the editable options for the meter design. All fields in this box are
editable with the exception of current resolution, voltage resolution, and power
resolution. These 3 boxes are set based on the following 3 tables.
These tables are important and are used to calculate the resolution values that are
used when calculating the _GLSB registers that occur while calibrating the meter.
It is these values that are also used to place the decimal point in the reading or results
frame.
The resolutions presented here are based on the assumption that the IMAX and VCAL
voltages will be at approximately 50% of the input voltage to the A/D converters. To
change the headroom of the A/D input simply change the MAXIMUM current number
and the GLSB registers will scale accordingly.
TABLE 6-2:
TABLE 6-3:
TABLE 6-4:
Note that the decimal point location in the reading frame is updated whenever the V
I
8.1
81
810
8,100
125
1,250
12,500
125,000
1,250,000
12,500,000
ALL
CAL
Maximum Wattage Less than or Equal To
Maximum Current Less than or Equal To
Maximum Voltage Less than or Equal To
, or I
MAX
(W - IMAX times VCAL)
values are changed.
CURRENT RESOLUTION TABLE
POWER RESOLUTION TABLE
VOLTAGE RESOLUTION TABLE
(A)
(V)
0.001
0.01
0.1
1
0.001
0.01
0.1
1
10
100
0.1
LSB Resolution
LSB Resolution
LSB Resolution
(mW)
(A)
(V)
© 2008 Microchip Technology Inc.
CAL
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