GXSC AFE Replaces ADS1291 in Eye Massagers

As modern people use their eyes more intensively, issues such as fatigue and stiffness in the muscles around the eyes are becoming increasingly common, making eye massagers an essential part of daily life for more and more people. Periorbital electromyographic (EMG) signals are faint bioelectric signals generated when periorbital muscles, such as the orbicularis oculi and levator palpebrae superioris, contract. The signal intensity and frequency characteristics directly correspond to muscle tension and contraction status. An analog front-end (AFE) chip is required to accurately detect and analyze these signals, enabling the massager to adapt to the user’s periorbital muscle condition and achieve effective eye care.

GXSC offers an application solution for smart eye massagers with EMG feedback. The bioelectric measurement analog front-end (AFE) chip in this solution features 24-bit high resolution and employs advanced low-noise design. Its integrated programmable gain amplifier (PGA) and digital filter effectively suppress noise interference, ensuring the accuracy of signal acquisition—a key advantage for capturing microvolt-level EMG signals.

 

For portable device applications, the GXSC AFE chip offers an ULP mode with a power consumption of just 0.475 mW per channel, significantly extending battery life. Its data buffering function reduces the number of MCU interrupts, helping to conserve system power. It also features lead detection based on a current sink/current source, with a current range of 6 nA to 399 nA, which can be adjusted according to product requirements.

Key features of the GXSC AFE include:

• 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 (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 driver, 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

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

• Flexible power-down and standby modes

• SPI interface

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