GXSC synchronous sampling ADC replaces AD7612 for spectral analysis

The core principle of spectral analysis is the interaction between matter and electromagnetic radiation (such as visible light, ultraviolet light, infrared light, etc.). When light is irradiated onto a substance, its atoms or molecules absorb, emit, or scatter light of specific wavelengths, resulting in characteristic spectra that can be used to identify and quantify elements or compounds in the substance.

The core requirements of ADC for spectral analysis are focused on high resolution, high-speed sampling, low noise, wide input range, and environmental adaptability. This article mainly introduces a GXSC single channel 16 bit 750kSPS synchronous sampling ADC applied to spectral analysis, fully adapting to the key features of spectral analysis. The main characteristics are as follows:

1. High resolution and excellent linearity ensure precise restoration of spectral signals

Spectral signals often contain weak intensity differences, especially in trace substance detection scenarios where signal amplitude variations are minimal, requiring ADCs to have sufficient resolution to capture these subtle differences. The GXSC ADC adopts a 16 bit successive pass architecture, achieving high-precision conversion of lossless codes. Through built-in calibration algorithms, the product has comprehensively improved its dynamic and static performance, with bipolar zero level errors as low as+2LSB and linearity below 1LSB.

2. High speed sampling capability to meet the requirements of fast scanning of wide spectra

In modern spectral analysis, in order to improve detection efficiency or capture dynamic spectral changes (such as spectral monitoring of rapid reaction processes), the system needs to have fast spectral scanning capabilities, which puts high demands on the sampling rate of ADC. The conversion rate of the GXSC ADC is as high as 750kSPS, greatly improving the detection efficiency of the entire spectral analysis system.

3. Flexible input range and configuration method, adaptable to diverse spectral signals

The amplitude of simulated signals generated by different types of spectral analysis varies, requiring ADCs to have a wide and configurable input range to adapt to different scenarios. The GXSC ADC only requires a 5V power supply and supports the conversion of true bipolar input signals of ± 10V and ± 5V. It has parallel or serial modes and can be configured through different connection modes of hardware pins. This function creates various connection conditions for the interface connection between the device and the microprocessor or DSP.

In order to simplify the PCB design of the data acquisition system, the GXSC ADC is equipped with an input buffer with a 1M Ω input impedance and an anti aliasing filter for direct acquisition of analog signals. It also integrates a high-precision reference voltage generator and buffer that can be flexibly configured. Its characteristics are as follows:

Adopting LQFP48 packaging, compatible with imported product AD7665

True bipolar analog input

Pin and software optional range: 5V, 10V, ± 5V, ± 10V

Throughput rate: 570kSPS

Low power consumption: 60mW (typical value)

Inoue, serial interface mode

High speed serial interface SPI/DSP

ENOB: 14.5 Bit (typical value)

SINAD: 89dB (typical value)

SFDR: 100dB (typical value)

INL: ± 1LSB (typical value)

DNL: ± 0.5 LSB (typical value)

Operating power consumption: 60 mW (typical value)