MCP3909RD-1PH1 Microchip Technology, MCP3909RD-1PH1 Datasheet - Page 45

• Manufacturer Part Number: MCP3909RD-1PH1
• Description: BOARD DES MCP3909 ENERGY METER
• Manufacturer: Microchip Technology

Specifications of MCP3909RD-1PH1

• Main Purpose: Power Management, Energy/Power Meter
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP3909, PIC18F85J90
• Primary Attributes: Single Phase Shunt Energy Meter
• Secondary Attributes: 16 Bit ADC
• Ic Function: Single Phase Energy Measurement IC
• Supply Voltage Range: 4.5V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: SSOP
• No. Of Pins: 24
• Interface Type: SPI
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

© 2009 Microchip Technology Inc.
5.3.9
The following equations represent the proper method for calculating the calibration and
correction factors for the RMS current and RMS voltage. The PC calibration software
handles these calculations automatically.
Typically, the V
For RMS Offset, the following equations apply:
EQUATION 5-19:
EQUATION 5-20:
EQUATION 5-21:
EQUATION 5-22:
EQUATION 5-23:
EQUATION 5-24:
EQUATION 5-25:
Note:
Equations for RMS Calibration
Convert to 16-bit signed integer for compatibility with PIC18F85J90 register
and firmware calculations
VR1
VR2
IR2
IR1
MIN
PHA_I_RMS_OFF
and I
=
=
=
=
PHA_I_RMS_RAW2 @ I
PHA_V_RMS_RAW2 @ I
PHA_I_RMS_RAW2 @ I
PHA_V_RMS_RAW2 @ I
MIN
voltages and currents will be 1/10 of the V
V
I
G
G
=
=
=
I
-------------------- -
I
V
---------------------- -
V
B
B
B
B
@ C1
@ C4
⎛
⎝
----------------------------------------------- -
@ C1
@ C4
--------------------------- -
IG IG 1
IR1 IR2
•
B
B
–
B
B
65536
, Configuration C1
, Configuration C4
, Configuration C1
, Configuration C4
Meter Calibration
–
⎞
⎠
–
IR
2
DS51884A-page 45
B
and I
B
values.