Four-channel 24-bit AFE GX1299 hardware and software replacement for ADS1299 in industrial transmitters

In industrial applications, transmitters typically serve as a critical component of measurement systems, working in close conjunction with sensors. Sensors are responsible for detecting the measured physical quantity and converting it into an analog signal, while transmitters further convert this analog signal into a standard signal for remote transmission and processing.

Core requirements analysis for industrial transmitters:

1. Ultra-high precision and low-noise acquisition

2. Multi-channel synchronous acquisition capability

3. Wide dynamic range and strong anti-interference performance

4. Low power consumption and high stability

The GX1299 is a 24-bit high-precision Σ-Δ ADC capable of achieving a signal-to-noise ratio (SNR) of up to 113 dB and a spurious-free dynamic range (SFDR) of 105 dB. In industrial pressure transmitter applications, its ultra-high resolution can precisely quantify the minute voltage changes output by pressure sensors, keeping pressure measurement errors within an extremely small range. The extremely low noise level enables this analog front end to effectively suppress background noise interference when acquiring weak signals, ensuring the accuracy and reliability of measurement data.

Key features of the GX1299:

• Data rate: 31.25 SPS to 32 kSPS

• Programmable gain: 1, 2, 3, 4, 6, 8, or 12

• Ultra-low input reference noise: 4.07 μVpp (0.64 μVrms) (BW = 150 Hz, G = 6)

• CMRR: 120 dB

• Flexible power consumption modes: High-Speed Mode (HS), Low-Power Mode (LP), Ultra-Low-Power Mode (ULP)

• In Low-Power Mode, power consumption is only 410 μW (AVDD = 3 V, DVDD = 1.8 V, ODR = 500 SPS, G = 6)

• Built-in low-temperature drift reference; built-in clock with adjustable frequency and external output capability

• Built-in driver amplifier, lead disconnection detection, temperature sensor, test signal

• Adjustable data buffer depth (1/2/4/8/16/32)

• Offset/Gain error calibration function

• Power supply range: Analog power supply: 2.7V to 5.25V; Digital power supply: 1.8V to 5.25V

• Flexible power-off and standby modes

• SPI interface

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