MCP3901A0-I/SS Microchip Technology, MCP3901A0-I/SS Datasheet
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MCP3901A0-I/SS Summary of contents
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... MCP3901 Low-Cost Power Monitor Reference Design 2010 Microchip Technology Inc. User’s Guide DS51915A ...
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... PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. ...
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... A.3 Board Schematic – Universal Serial Bus ..................................................... 24 A.4 Board – Top Trace and Top Silk .................................................................. 25 A.5 Board – Bottom Trace and Bottom Silk ........................................................ 25 Appendix B. Bill of Materials Worldwide Sales and Service .................................................................................... 30 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR USER’S GUIDE Table of Contents DS51915A-page 3 ...
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... NOTES: DS51915A-page 4 2010 Microchip Technology Inc. ...
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... Appendix A. “Schematics and Layouts”– Shows the schematic and board layouts for the MCP3901 Low-Cost Power Monitor Reference Design. • Appendix B. “Bill of Materials” – Lists the parts used to build the MCP3901 Low-Cost Power Monitor. 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR REFERENCE DESIGN Preface NOTICE TO CUSTOMERS ® ...
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... Optional arguments mcc18 [options] file [options] Choice of mutually exclusive errorlevel {0|1} arguments selection Replaces repeated text var_name [, var_name...] Represents code supplied by void main (void) user { ... } 2010 Microchip Technology Inc. Examples ® IDE User’s Guide ...
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... Local sales offices are also available to help customers. A listing of sales offices and locations is included in the back of this document. Technical support is available through the web site at http://support.microchip.com. DOCUMENT REVISION HISTORY Revision A (November 2010) Initial release of this document. 2010 Microchip Technology Inc. DS51915A-page 7 ...
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... NOTES: DS51915A-page 8 2010 Microchip Technology Inc. ...
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... Dual ADC MCP3901 output display using serial communication to the PC software interface • MCP3901 ADC ability to do simultaneous sampling; with sampling speed ksps, and 91 dB SINAD • Computation of U FIGURE 1-1: 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR REFERENCE DESIGN ), Active Power, Apparent Power, and Power RMS , I ...
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... Because the MCU does not include an LCD driver, the LCD used in this reference design has the driver built in. The connection between the LCD and the MCU carries four lines of data and three lines of control. DS51915A-page 10 pin. For better noise rejection on REF 2010 Microchip Technology Inc. ...
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... Initially, the acquired samples go through a first-order Infinite Impulse Response high-pass filter (IIR HPF), which has the following roles: 1. Removes the offset of the ADC 2. Compensates for the Sinc filters transfer function 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR REFERENCE DESIGN Active Power Scaling Factor ...
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... DS51915A-page 12 and I RMS RMS 2 2 and I . For the integrated values, the samples v[ First-Order IIR Filter Structure. RMS , the acquired samples are multiplied , a RMS y[ y[n- Power Factor, and Active RMS RMS 2010 Microchip Technology Inc. , ...
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... Once written into the MCP3901 ADC Phase Delay register, the Phase Delay block inside the MCP3901 ADC compensates for power-factor-related errors. This method decreases the computation requirement on the PIC18F25K20 MCU. 2010 Microchip Technology Inc. Error VS Angle VS Phase Delay Register (kk) 0.25 ...
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... Depending on the sampling speed of the ADC, this low-pass filter can be narrower or wider. Figure 2-4 shows the following line frequency situations: • 880 sps (as in this meter) • 1200 sps • 3200 sps FIGURE 2-4: Sinc Filters Transfer Functions. DS51915A-page 14 2010 Microchip Technology Inc. ...
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... Hz. The measurement differences can be higher than 0.2%. To have accurate measurements, without regard for the line frequency necessary to compensate for these low-pass filter situations. FIGURE 2-5: Errors Caused by Line Frequency. 2010 Microchip Technology Inc. DS51915A-page 15 ...
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... HPF will compensate the Sinc transfer function to approximately the 50 Hz value. The simulation and the measurements indicate that a cutoff frequency for the HPF is the best choice in this case (see Figure 2-6). FIGURE 2-6: Sinc Filter Compensation Using HPF. DS51915A-page 16 2010 Microchip Technology Inc. ...
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... HPF has a lower cutoff frequency. This extra attenuation slightly increases the measurement errors at low currents in which mea- surement is made more difficult because of the lower signal-to-noise ratio (SNR). In this situation, the accuracy decrease is less than 0.1% and is considered acceptable. 2010 Microchip Technology Inc ...
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... Figure 2-3. DS51915A-page 18 induce an extra phase delay on the other channel, so the phase Power Factor Compensation Equation -0.4 -0 Measurement Variation (%) -4 Influence of the Phase Delay Register Over Measurement induced by the various compo- 0.2 0.4 0 4.9693x - 0.9836 2010 Microchip Technology Inc. ...
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... EEPROM. Now power can be disconnected from the meter. The two power values measured at -45 and +45 degrees are inserted into the equation in Figure 2-8, and the result is the Phase Delay register value required to compensate for the power factor variation. 2010 Microchip Technology Inc and Phase RMS ...
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... NOTES: DS51915A-page 20 2010 Microchip Technology Inc. ...
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... Board Schematic – Microcontroller and LCD • Board Schematic – Universal Serial Bus • Board – Top Trace and Top Silk • Board – Bottom Trace and Bottom Silk 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR REFERENCE DESIGN DS51915A-page 21 ...
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... A.1 BOARD SCHEMATIC – ANALOG AND POWER DS51915A-page 22 2010 Microchip Technology Inc. ...
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... A.2 BOARD SCHEMATIC – MICROCONTROLLER AND LCD 2010 Microchip Technology Inc. DS51915A-page 23 ...
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... A.3 BOARD SCHEMATIC – UNIVERSAL SERIAL BUS DS51915A-page 24 2010 Microchip Technology Inc. ...
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... A.4 BOARD – TOP TRACE AND TOP SILK MCP 3901 A.5 BOARD – BOTTOM TRACE AND BOTTOM SILK 2010 Microchip Technology Inc. DANGER HIGH VOLTAGE PIC18F25K20 POWER METER DS51915A-page 25 ...
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... NOTES: DS51915A-page 26 2010 Microchip Technology Inc. ...
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... RES 220 OHM 1/8W 1% 0805 R37, R40 SMD Note 1: The components listed in this Bill of Materials are representative of the PCB assembly. The released BOM used in manufacturing uses all RoHS-compliant components. 2010 Microchip Technology Inc. MCP3901 LOW-COST POWER MONITOR REFERENCE DESIGN Manufacturer Yageo Corporation AVX Corporation ...
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... MCP1703T-3302E/DB Microchip Technology Inc. MCP1703T-3302E/DB Microchip Technology Inc. PIC18F14K50-E/SS Fairchild Semiconductor H11A8173S Analog Devices, Inc. ADUM1201CRZ-RL7 Microchip Technology Inc. MCP131T-270I/TT Microchip Technology Inc. PIC18F25K20-E/SS Vishay DRALORIC CRCW2512100RFKEG Yageo Corporation RC1206FR-07330KL Abracon Corporation ABM3B-16.000MHZ-B2-T Abracon Corporation ABM3B-12.000MHZ-B2-T 2010 Microchip Technology Inc. ...
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... NOTES: 2010 Microchip Technology Inc. DS51915A-page 29 ...
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... Philippines - Manila Tel: 63-2-634-9065 Fax: 63-2-634-9069 Singapore Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan - Hsin Chu Tel: 886-3-6578-300 Fax: 886-3-6578-370 Taiwan - Kaohsiung Tel: 886-7-213-7830 Fax: 886-7-330-9305 Taiwan - Taipei Tel: 886-2-2500-6610 Fax: 886-2-2508-0102 Thailand - Bangkok Tel: 66-2-694-1351 Fax: 66-2-694-1350 2010 Microchip Technology Inc. 08/04/10 ...