ADI AD7768八路同时取样Σ－Δ ADC解决方案

ADI公司的AD7768是每路都集成了Σ-Δ调制器和数字滤波器的八路同时取样Σ-Δ模数转换器(ADC),最大输入带宽110.8kHz时的动态范围108dB, INL ±2 ppm,失调误差±50 μV,增益误差±30 ppm,每路的ADC数据输出速率256 kSPS,主要用在数据采集系统如USB/PXI/以太网,仪器和工业控制回路,音频测试和测量,三相电源质量分析,声呐,高精度医疗EEG/EMG/ECG以及振动和资产监测.本文介绍了AD7768主要特性,功能框图,以及评估板EVAL-AD7768FMCZ主要特点,电路图,材料清单和PCB设计图.
The AD7768 is an 8-channel, simultaneous sampling Σ-Δ analog-to-digital converter (ADC) with a Σ-Δ modulator and digital filter per channel, enabling synchronized sampling of ac and dc signals.
The AD7768 achieves 108 dB dynamic range at a maximum input bandwidth of 110.8 kHz, combined with typical performance of ±2 ppm integral nonlinearity (INL), ±50 μV offset error, and ±30 ppm gain error.
The AD7768 user can trade off input bandwidth, output data rate, and power dissipation. Select one of three power modes to optimize for noise targets and power consumption. The flexibility of the AD7768 allows it to become a reusable platform for low power dc and high performance ac measurement modules.
The AD7768 has three modes: fast mode (256 kSPS maximum, 110.8 kHz input bandwidth, 51.5 mW per channel), median mode (128 kSPS maximum, 55.4 kHz input bandwidth, 27.5 mW per channel) and eco mode (32 kSPS maximum, 13.8 kHz input bandwidth, 9.375 mW per channel).
The AD7768 offers extensive digital filtering capabilities, such as a wideband, low ±0.005 dB pass-band ripple, antialiasing low-pass filter with sharp roll off, and 105 dB attenuation at the Nyquist frequency.
Frequency domain measurements can use the wideband linear phase filter. This filter has a flat pass band (±0.005 dB ripple) from dc to 102.4 kHz at 256 kSPS, from dc to 51.2 kHz at 128 kSPS, or from dc to 12.8 kHz at 32 kSPS.
The AD7768 also offers sinc response via a sinc5 filter, a low latency path for low bandwidth, and low noise measurements.
The wideband and si...