GXSC Analog-to-Digital Converter Software and Hardware Replacement for ADS1274 in Vibration Detection

Vibration detection is a critical technology for evaluating the performance and reliability of mechanical systems, primarily by monitoring and analyzing vibration signals to identify potential issues. It employs sensors to monitor vibration behavior within mechanical systems, enabling the identification of potential problems for maintenance and repair. While vibration is a normal phenomenon in mechanical operation, exceeding set parameters may lead to equipment failure or performance degradation. Vibration detection helps enhance the reliability and performance of mechanical equipment.

When collecting vibration signals during equipment operation, considerations include signal weakness, broad frequency range, and multi-component superposition characteristics. Simultaneous acquisition from multiple measurement points is required to analyze phase relationships, demanding high precision, synchronization, anti-interference capability, and environmental adaptability from the acquisition system. This paper recommends using GXSC‘s 24-bit synchronous sampling analog-to-digital converter, which can replace the ADS1274 to provide highly reliable multidimensional vibration signals. The chip‘s advantages over the ADS1274 are as follows:

Higher Signal-to-Noise Ratio:

- Two additional filter options

- 3dB higher in wideband filter mode

- 5dB higher in low-latency filter mode

Ultra-Low Distortion Performance:

- High-resolution mode achieves 116dB

- Approximately 8dB improvement in common-mode rejection ratio

Extremely Low Power Consumption:

- 40% reduction in power consumption

The device employs a high-order multi-bit Delta-sigma modulator that shapes in-band noise before filtering it through an on-chip digital decimation filter, achieving exceptionally low in-band noise power. Two on-chip digital filters are selectable: A high-bandwidth FIR filter with an effective bandwidth reaching 90.6% of the Nyquist bandwidth and in-band ripple less than ±0.005dB; or a low-latency SINC filter that generates stable data output within 6 cycles with superior noise performance.

To accommodate diverse applications, this GXSC ADC offers four selectable modes based on speed, precision, and power requirements: High-Speed (HS) mode delivers peak performance at 144 kSps with a 37 MHz clock and -3 dB bandwidth of 70 kHz; High-Resolution (HR) mode: Highest precision with SNR up to 111.7dB, THD down to -122.9dB, and power consumption of only 20.8mW/channel; Low-Power (LP) mode: Same output rate as HR mode but with nearly halved power consumption; Low-Speed (LS) mode: Suitable for low-speed acquisition with power consumption as low as 2.7mW/channel. The chip is directly controlled via PIN pins, eliminating the need for register compilation and simplifying customer usage.

The GXSC ADC features:

4-channel synchronous sampling with data rates up to 144kSps

Selectable high-bandwidth FIR filter or low-latency SINC filter

Low power consumption: HS mode: 34.0 mW/channel; HR mode: 20.8 mW/channel; LP mode: 10.9 mW/channel; LS mode: 2.7 mW/channel

Rail-to-rail input common-mode level

Common-mode rejection ratio: 116 dB

Analog power supply: 5V; Digital power supply: 1.8V

I/O power supply: 1.8V to 3.3V

SPI or frame synchronous interface, supports daisy chain mode

ESD rating: HBM ±2kV, CDM ±2kV; Latch-up ±600mA

Operating temperature range: -40°C to +85°C