Microchip MCP3909 16位ADC评估方案

Microchip公司的 MCP3909是双路16位delta-sigma ADC,支持IEC 62053和以前的IEC 1036/61036/687国际能量标准.数字波形数据接入通过SPI接口,16位双ADC数据输出字,20位乘法器输出数据字,动态范围1000:1的能量测量误差为0.1%,用于小信号输入的PGA支持低数值并联电流传感器,片内基准具有超低的温漂15ppm/度C.MCP3909 ADC评估板用于16位MCU系统接口,提供16位基于PIC的应用开发平台.本文介绍了MCP3909的主要特性和方框图,以及MCP3909 ADC评估板的主要性能,方框图以及详细电路图和材料清单(BOM).

The MCP3909 device is an energy-metering IC designed to support the IEC 62053 international metering standard specification. It supplies a frequency output proportional to the average active real power, with simultaneous serial access to ADC channels and

multiplier output data. This output waveform data is available at up to 14 kHz with 16-bit ADC output and 20-bit multiplier output words. The 16-bit, delta-sigma ADCs allow for a wide range of IB and IMAX currents and/or small shunt (<200 μOhms) meter designs. A noload threshold block prevents any current creep measurements for the active power pulse outputs. The integrated on-chip voltage reference has an ultra-low temperature drift of 15 ppm per degree C.This accurate energy metering IC with high field reliability is available in the industry standard 24-lead SSOP pinout.

MCP3909特性和亮点:

Supports IEC 62053 International Energy Metering Specification and legacy IEC 1036/
61036/687 Specifications

Digital waveform data access through SPI interface

16-bit Dual ADC output data words

20-bit Multiplier output data word

Dual functionality pins support serial interface access and simultaneous Active Power Pulse Output

Two 16-bit second order delta-sigma Analog-to- Digital Converters (ADCs) with multi-bit DAC

81 dB SINAD (typ.) both channels

0.1% typical active energy measurement error over 1000:1 dynamic range

PGA for small signal inputs supports low value shunt current sensor

Ultra-low drift on-chip reference: 15 ppm/℃(typ.)

Direct drive for electromagnetic mechanical counter and two-phase stepper motors

Low IDD of 4 mA (max.)

Tamper output pin for negative power indication

Industrial Temperature Range: -40℃ to +85℃



图1. MCP3909方框图

MCP3909 ADC评估板

The MCP3909 ADC Evaluation Board for 16-Bit MCUs system provides the ability to evaluate the performance of the MCP3909 dual channel ADC. It also provides a development platform for 16-bit PIC based applications, using existing 100-pin PIM systems compatible with the Explorer-16 and other high pincount PIC demo boards. The system comes with programmed PIC24FJ128GA010 and dsPIC33FJ256GP710 PIM modules that communicate both to on-board LCD and a LabView GUI for both in-circuit and PC signal processing.



图2.MCP3909评估板方框图



图3.MCP3909评估板电路图(1)



图4.MCP3909评估板电路图(2)



图5.MCP3909评估板电路图(3)



图6.MCP3909评估板电路图(4)



图7.MCP3909评估板电路图(5)



图8.MCP3909评估板电路图(6)

MCP3909评估板材料清单(BOM):