GXSC ADC Replaces AD7685 in Data Loggers

Data loggers are primarily responsible for the real-time acquisition, digital conversion, and local storage of various analog sensor signals. They consist of an analog sensor front end, a signal conditioning unit, a high-precision ADC acquisition unit, a main control processing unit, and a storage unit, forming a complete acquisition chain. Analog signals from the sensor acquisition site are fed into the high-precision ADC to complete the analog-to-digital conversion.

To enhance the accuracy, continuity, and stability of acquired data, as well as the device’s battery life, the GXSC single-channel 16-bit 250 kSPS analog-to-digital converter is specifically designed for low-frequency precision acquisition and long-term monitoring scenarios, fully meeting the requirements of data logger applications. The chip integrates a zero-loss sampling core, adaptive power management, daisy-chain interface, and a low-noise analog front end, addressing the issues of low accuracy, high power consumption, and poor stability found in traditional data loggers.

Combines high precision with speed: It offers true 16-bit resolution and maintains excellent linearity even at sampling rates as high as 250 kSPS. Its typical integral nonlinearity (INL) is only ±0.6 LSB (maximum ±2 LSB), equivalent to ±0.003% of full scale, ensuring conversion accuracy.

Exceptional dynamic performance: At an input frequency of 20 kHz, the signal-to-noise ratio (SNR) reaches 82 dB, and total harmonic distortion (THD) is as low as –100 dB, making it ideal for applications requiring high-fidelity signal acquisition.

Flexible pseudo-differential input: The pseudo-differential input architecture covers an input range from 0 V to REF, where the reference voltage REF can be externally set (up to the supply voltage VDD). This design offers the advantage of differential input for common-mode noise suppression while simplifying the interface design for single-ended signals.

GXSC ADC Features:

Internal Nonlinearity (INL): Typical ±0.6 LSB, Maximum ±2 LSB

Signal-to-Noise Ratio (SNR): 82 dB

Total Harmonic Distortion (THD): -100 dB

Pseudo-differential analog input range: 0 V to VREF (VREF is at most VDD)

No pipeline delay

Single-supply operation: 2.3 V to 5.5 V; logic interface voltage: 1.8 V to 5 V

Serial interface: SPI®/QSPI™/MICROWIRE™/DSP-compatible

Daisy-chain connection of multiple ADCs; busy/idle indication

Operating temperature: -55°C to +125°C

Package: MSOP10