The Application of High-Precision Analog-to-Digital Converter GX1278 Replacing ADS1278 in Multi-Channel Data Acquisition

A multi-channel data acquisition system serves as the infrastructure for achieving precise sensing. It requires the simultaneous synchronous collection of multiple physical quantities (such as temperature, pressure, vibration, voltage, etc.), converting analog signals into digital signals to provide reliable data for subsequent analysis. The accuracy, synchronization, and stability of multi-channel data acquisition directly determine the overall system performance. This paper recommends the 24-bit, eight-channel, 256KSPS high-precision analog-to-digital converter GX1278. The chip is pin-to-pin compatible with TI‘s ADS1278, offering cost advantages and stable supply channels through GXSC.

The GX1278 is a 24-bit analog-to-digital converter based on the Delta-Sigma architecture. During data acquisition, the chip‘s data output rate can support up to 256KSPS. It includes internal functional modules such as Delta-Sigma modulator, digital filter, serial data output, clock, logic control, and 10 ports.

Synchronous sampling is one of the core requirements for multi-channel data acquisition, especially in scenarios where analyzing the correlation of multiple physical quantities is necessary. Sampling delays between channels can lead to data distortion and compromise the accuracy of analysis results. The GX1278 synchronous signal enables strict synchronous sampling across 8 channels, ensuring all channels capture signals simultaneously and completely eliminates time deviations between channels. It supports cascaded output data and external synchronization, facilitating its application in situations where the ADC demand exceeds 8 channels.

The GX1278 not only achieves precise DC measurement characteristics but also maintains high-level AC performance. The chip offers five operating modes—ultra-high speed, high speed, high precision, low power, and low speed—for user selection, with corresponding modes accessible via hardware configuration of relevant pins. The on-chip digital filter converts the oversampled signal output by the analog Delta-Sigma modulator into a low-noise digital signal. Additionally, GX1278 data can be read via serial interfaces, supporting both SPI and Frame-Sync protocols.

Introduction to the Advantages of GX1278:

1. Product dimensions, pin functions are compatible with reference models, supporting pin-to-pin replacement for ADS1278

2. Higher sampling rate, up to 256KSPS

3. Low power consumption, no need for a heat sink

4. Low Sampling Aperture Error