MCP3909RD-3PH3 Microchip Technology, MCP3909RD-3PH3 Datasheet - Page 27

• 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

3.1
3.2
© 2009 Microchip Technology Inc.
OVERVIEW
MAIN LOOP
This section discusses the dsPIC firmware structure, peripheral resources, important
program flows, and explanations of project files included in the firmware zip files
included with the system. See Appendix D. “50/60 Hz Meter Operation” for
converting to 60 Hz code.
• Calculate all electrical parameters in frequency domain
• MCP3909 device communication
• Detect voltage/current phase order, and determine missing phases
• Generation imp/kWh power pulse
• UART communication
The main loop of the entire dsPIC33F program is shown in Figure 3-1.
FIGURE 3-1:
ENERGY METER REFERENCE DESIGN
Chapter 3. Firmware
Initialize on-chip
peripherals and variables
and MCP3909 device
acquisition complete?
Process UART
comm. commands
Sampled 3 cycles?
Main Loop Chart.
Main Program
Clear WDT
Neutral data
MCP3909 / DSPIC33F 3-PHASE
No
No
Yes
Yes
Calculation()
Compute elec.
parameters
Compute
neutral line
current
DS51723A-page 27