GXSC AFE Replaces ADS1294R in Respiratory Monitoring Devices

Respiratory monitors are essential tools in modern medicine and health management, playing a vital role in various fields such as clinical care, home care, and sports health. By regularly tracking and recording respiratory data, they provide users with detailed information about their respiratory status, helping them identify and address potential respiratory issues in a timely manner and take effective measures to improve respiratory health.

Respiratory monitors can monitor key indicators such as an individual’s respiratory rate, depth, and oxygen saturation in real time, supporting the assessment of respiratory health. When the device acquires human respiratory signals, it requires multi-channel synchronous sampling capabilities, eliminating the need for additional ADCs and further simplifying circuit design. The GXSC four-channel 24-bit analog front-end (AFE) chip is specifically designed for bioelectrical signal acquisition. Its standout feature is the integrated respiratory impedance measurement capability, eliminating the need for additional dedicated respiratory sensors, making it highly suitable for respiratory monitoring applications.

The GXSC AFE can accurately acquire bioelectric signals such as EEG, ECG, and EMG. It offers 100% hardware and software compatibility with the ADS1294R for use in respiratory monitoring device solutions. It also features respiratory detection, right-leg drive, lead disconnection detection, pacing detection, and WCT functions. It can switch to an internal clock and internal reference, thereby simplifying the ECG peripheral circuitry and significantly reducing the size, power consumption, and cost of the application.

The GXSC AFE integrates a programmable gain amplifier, an internal reference, and an internal oscillator. By configuring the multiplexer, users can select the signal connected to the ADC’s main channel to perform offset testing, temperature monitoring, power supply measurement, and channel testing, facilitating easier monitoring of the chip and product operating environment. Its key features are as follows:

• 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 modes: High-Speed (HS), Low-Power (LP), and Ultra-Low-Power (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-drift reference; built-in clock with adjustable frequency and external output capability

• Built-in right-lead drive amplifier, lead disconnection detection, temperature sensor, and test signal

• Supports digital pacing detection

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

• Offset/Gain error calibration function

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

• Flexible power-down and standby modes

• SPI interface

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