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ADC" title="ADC">ADC" title="ADC">ADC,两个PGA,相位延迟补偿区块,低漂移基准电压,调制输出区块,数字失调和增益误差校正寄存器以及高速20MHz SPI兼容串口.每路有 94.5 dB SINAD, -106.5 dBc THD, 111 dB SFDR,2.7-3.6V工作电压,可编数据速率高达125 ksps,主要用在能量和功率测量,汽车,手持仪表,医疗和电源监视以及音/视频识别.本文介绍了MCP3911主要特性,方框图以及用于16位MCU的MCP3911 ADC评估板主要特性, 和PIM MCU连接框图,电路图,材料清单和PCB元件布局图.
The MCP3911 is a 2.7V to 3.6V dual channel Analog Front End (AFE) containing two synchronous sampling Delta-Sigma Analog-to-Digital Converters (ADC), two PGAs, phase delay compensation block, low-drift internal voltage reference, modulator output block, digital offset and gain errors calibration registers, and high-speed 20 MHz SPI compatible serial interface.
The MCP3911 ADCs are fully configurable with features such as: 16/24-bit resolution, OSR from 32 to 4096, gain from 1x to 32x, independent shutdown and reset, dithering and auto-zeroing. The communication is largely simplified with the one-byte-long commands including various continuous read/write modes that can be accessed by the Direct Memory Access (DMA) of an MCU, and with a separate data ready pin that can be directly connected to an Interrupt Request (IRQ) input of an MCU.
The MCP3911 is capable of interfacing a large variety of voltage and current sensors including shunts, current transformers, Rogowski coils and Hall effect sensors.
MCP3911主要特性:
• Two Synchronous Sampling 16/24-bit Resolution Delta-Sigma A/D Converters
• 94.5 dB SINAD, -106.5 dBc Total Harmonic Distortion (THD) (up to 35th harmonic), 111 dB SFDR for Each Channel
• 2.7V - 3.6V AVDD, DVDD
• Programmable Data Rate up to 125 ksps
4 MHz Maximum Sampling Frequency
• Oversampling Ratio up to 4096
• Ultra Low Power Shutdown Mode with <2 μA
• -122 dB Crosstalk between the Two Channels
• Low Drift 1.2V Internal Voltage Reference: 7 ppm/℃
• Differential Voltage Reference Input Pins
• High Gain PGA on Each Channel (up to 32V/V)
• Phase Delay Compensation with 1 μs Time Resolution
• Separate Modulator Output Pins for Each Channel
• Separate Data Ready Pin for Easy Synchronization
• Individual 24-bit Digital Offset and Gain Error Correction for Each Channel
• High-Speed 20 MHz SPI Interface with Mode 0,0 and 1,1 Compatibility
• Continuous Read/Write Modes for Minimum Communication
• Low Power Consumption (8.9 mW at 3.3V, 5.6 mW at 3.3V in low-power mode, typical)
• Available in Small 20-lead QFN and SSOP Packages, Pin-to-pin Compatible with MCP3901
• Extended Temperature Range: -40℃ to +125℃
MCP3911应用:
• Energy Metering and Power Measurement
• Automotive
• Portable Instrumentation
• Medical and Power Monitoring
• Audio/Voice Recognition
图1.MCP3911方框图
用于16位MCU的MCP3911 ADC评估板
MCP3911 ADC Evaluation Board for 16-Bit MCUs
The MCP3911 ADC Evaluation Board for 16-Bit MCUs system provides the opportunity to evaluate the performance of the MCP3911 dual-channel ADC. It also provides a development platform for 16-bit PIC®-based applications, using existing 100-pin PIC microcontroller Plug-in Module (PIM) systems that are compatible with the Explorer 16 and other high pin count PIC®-based demo boards. The system comes with a programmed PIC24FJ256GA110 PIM module that communicates with the Energy Management Utility software for data exchange and ADC setup.
MCP3911 ADC评估板亮点:
• Dual ADC MCP3911 output display using serial communication to the PC software interface
• Simultaneous 55 ksps at OSR32 address loop ALL or 95 dB SINAD at OSR512 performance on MCP3911
• System and ADC performance analysis through graphical PC tools showing noise histogram, frequency domain (FFT), time domain scope plot, and statistical numerical analysis
• Robust hardware design with analog grounding and analog/digital separation, allowing low noise evaluation of MCP3911 devices; includes separate power supplies and power planes on a 4-layer board.
• PICtail™ Plus connectors for Explorer 16 daughter board compatibility
图2.MCP3911评估板外形图
图3.MCP3911和PIM MCU连接框图
图4.MCP3911评估板电路图:ADC和电源
图5.MCP3911评估板电路图:MCU
图6.MCP3911评估板电路图:PIM模块
图7.MCP3911评估板电路图:LCD和UART
MCP3911评估板材料清单:
图8.MCP3911评估板PCB布局图:顶层
图9.MCP3911评估板PCB布局图:底层
图10.MCP3911评估板元件布局图:顶层
图11.MCP3911评估板元件布局图:底层
详情请见:
http://ww1.microchip.com/downloads/en/DeviceDoc/22286A.pdf
和
http://ww1.microchip.com/downloads/en/DeviceDoc/52033A.pdf
