Microchip业界首个三相电表六路AFE解决方案

发布时间:2012-05-3 阅读量:1892 来源: 我爱方案网 作者:

中心议题:
    *  Microchip六路模拟前端(AFE)介绍
解决方案:
    *  Microchip三相电能表解决方案


Microchip公司的MCP3903是业界首个用于三相电表的六路模拟前端(AFE),包括三对两个带PGA同步取样Delta-Sigma的16/24位ADC,相位延迟补偿区块,基准电压以及SPI兼容的高速10MHz串行接口.转换器中的抖动算法能降低闲音(idle tones),改善THD,SINAD为91dB,THD为-100dBc,SFDR为102dB,可编程数据速率高达64ksps,关断模式功耗小于2uA,任意两路间串扰为-115dB,内部基准电源的温票为5 ppm/°C,主要用在电表和能量测量,手提仪表以及医疗和电源监视等.本文介绍了MCP3903主要特性,功能方框图以及用于16位MCU的MCP3903 ADC评估板亮点,电路图和材料清单与PCB元件布局图.

Microchips First Six-Channel Analog Front End for Three-Phase Energy Metering Offers Industry-Leading Accuracy Microchip.

The MCP3903 is a six-channel Analog Front End (AFE) containing three pairs made out of two synchronous sampling Delta-Sigma Analog-to-Digital Converters (ADC) with PGA, a phase delay compensation block, internal voltage reference, and high-speed 10 MHz SPI compatible serial interface. The converters contain a proprietary dithering algorithm for reduced idle tones and improved THD.

The internal register map contains 24-bit wide ADC data words, a modulator output register as well as six 24-bit writable control registers to program gain, over-sampling ratio, phase, resolution, dithering, shut-down, reset and several communication features.

The communication is largely simplified with various Continuous Read modes that can be accessed by the Direct Memory Access (DMA) of an MCU and with separate Data Ready pins that can directly be connected to the Interrupt Request (IRQ) input of an MCU. The MCP3903 is capable of interfacing to a large variety of voltage and current sensors including shunts, current transformers, Rogowski coils, and Hall-effect Sensors.

MCP3903主要特性:

• Six Synchronous Sampling 16/24-bit Resolution Delta-Sigma A/D Converters with Proprietary Multi-Bit Architecture

• 91 dB SINAD, -100 dBc Total Harmonic Distortion (THD) (up to 35th harmonic), 102 dB Spurious-free Dynamic Range (SFDR) for Each Channel

• Programmable Data Rate up to 64 ksps

• Ultra Low-Power Shutdown Mode with <2 μA

• -115 dB Crosstalk Between any Two Channels

• Low Drift Internal Voltage Reference: 5 ppm/°C

• Differential Voltage Reference Input Pins

• High Gain PGA on Each Channel (up to 32 V/V)

• Phase Delay Compensation Between Each Pair of Channels with 1 μs Time Resolution

• High-Speed Addressable 10 MHz SPI Interface with Mode 0,0 and 1,1 Compatibility

• Independent Analog and Digital Power Supplies 4.5V - 5.5V AVDD, 2.7V - 3.6V DVDD

• Available in Small 28-lead SSOP Package

• Extended Temperature Range: -40°C to +125°C

MCP3903应用:

• Energy Metering and Power Measurement
 

• Portable Instrumentation

• Medical and Power Monitoring

图1.MCP3903功能方框图

用于16位MCU的MCP3903 ADC评估板

The MCP3903 ADC Evaluation Board for 16-Bit MCUs system lets users evaluate the performance of the MCP3903 six-channel ADC. It also provides a development platform for 16-bit PIC® MCU-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 PIM modules that communicate with the LabView GUI for data exchange and ADC setup.

MCP3903 ADC评估板亮点:

• Six-channel ADC MCP3903 output display using serial communication to the PC Software Interface and LCD

• Simultaneous 4 ksps at 91 dB Signal-to-Noise and Distortion Ratio (SINAD) performance. The ADC can run up to 64 ksps.

• System and ADC performance analysis through graphical PC tools showing Time domain scope plot, Frequency Domain (FFT), and statistical numerical analysis.
 

• Robust hardware design with analog grounding and analog/digital separation, allowing low noise evaluation of the MCP3903 devices. Separate power supplies and power planes - 4 layer board.

• Pigtail Plus connectors for Explorer-16 daughter board compatibility.

图2.MCP3903 ADC评估板外形图

图3.MCP3903 ADC评估板电路图(1):模拟

图4.MCP3903 ADC评估板电路图(2):LCD和UART
 


图5.MCP3903 ADC评估板电路图(3):USB和存储器

图6.MCP3903 ADC评估板电路图(4):MCU

图7.MCP3903 ADC评估板电路图(4):PIM模块
 


图8.MCP3903 ADC评估板电路图(5):电源

图9.MCP3903 ADC评估板元件布局图:正面

图10.MCP3903 ADC评估板元件布局图:背面
 

MCP3903 ADC评估板材料清单:

相关资讯
HBM4制程技术竞赛白热化 三星重注1c工艺布局高端存储市场

在全球高端存储芯片产业格局加速重构的背景下,HBM4技术研发已成为DRAM三巨头战略博弈的核心战场。三星电子近期公布的产能扩张计划显示,该公司正通过大规模技术投资构建差异化竞争优势,力图在下一代高带宽存储器领域实现弯道超车。

国产高精度运放崛起:解析RS8531/2如何攻克微弱信号处理难题

随着工业4.0和智能传感技术的快速发展,高精度运算放大器(运放)作为信号链的核心器件,其性能直接影响精密测量系统的可靠性。2025年,润石科技推出的RS8531/2系列超低噪声、零漂移运放,以0.15μVpp的1/f噪声和1.2μV失调电压的突破性参数,展现了国产半导体企业在高端模拟芯片领域的技术实力。该产品不仅对标国际大厂同类器件,更在多个关键技术指标上实现超越,成为精密仪器、医疗设备等领域的优选方案。

苹果折叠屏手机+AR眼镜双线出击:2026产品矩阵首曝光

全球消费电子产业迎来重大技术革新,苹果公司近日被曝出正在加速推进其首款人工智能穿戴设备的研发进程。据彭博社援引知情人士消息称,苹果工程师团队正致力于在2026年底推出代号N401的智能眼镜产品,该设备将集成摄像头阵列、定向麦克风及骨传导扬声器系统,通过深度融合环境感知与AI运算能力重新定义人机交互方式。

汽车智能化催生高可靠性供电需求,豪威推出四通道高边开关芯片

2024年5月23日,豪威集团(OmniVision)宣布推出车规级智能高边开关芯片ONXQ000系列,计划于2025年6月投入量产。该产品针对车载摄像头、超声波雷达等传感器在智能驾驶与数字座舱中的供电痛点,通过四通道集成设计、ASIL-B功能安全认证及创新负压保护技术,为域控制器供电方案提供更高安全性与灵活性。

半导体巨头组织重构引发产业格局猜想:三星代工业务分拆可行性分析

据韩国半导体行业媒体5月22日报道,三星电子半导体部门(DS Division)正面临战略性抉择。继三星生物制剂拆分CDMO业务后,市场对三星晶圆代工业务独立运营的预期显著升温。当前决策的核心矛盾源于客户企业对"设计与制造一体化"模式的信任危机,以及该部门持续亏损的经营现状。