Replace ADS8568 with GX8568 eight-channel 16-bit 510 kSPS simultaneous-sampling ADC for inertial measurement units

In the design of inertial measurement units (IMUs), the output signal quality of gyroscopes and accelerometers directly determines attitude calculation and navigation accuracy. An IMU usually includes a three-axis gyroscope, a three-axis accelerometer, and temperature sensors for temperature compensation. How to perform high-precision, low-phase-mismatch synchronous acquisition of these analog signals is a key part of hardware design. The GX8568 can replace the ADS8568 to meet the needs of this kind of multi-sensor synchronous acquisition.

A typical IMU includes six inertial sensor outputs (three gyroscope channels and three accelerometer channels). In addition, two temperature sensor channels are usually required for temperature compensation of zero bias and scale factor, totaling eight analog signals. This exactly matches the eight-channel analog-to-digital converter configuration of the GX8568. The eight channels sample simultaneously, avoiding the inter-channel time skew introduced by time-division sampling and eliminating the cross-coupling error caused by inconsistent sampling timing.

The GX8568 has a conversion rate of up to 510 kSPS per channel and can support true bipolar input signals of up to ±10 V with only a 5 V power supply. To simplify the PCB design of the data acquisition system, the GX8568 integrates an input buffer with 1 MΩ input impedance and an anti-aliasing filter, making it convenient to directly acquire analog signals. It also integrates a flexibly configurable high-precision reference voltage generator and buffer.

GX8568 product advantages:

ENOB: 14.6 Bit (typical)

SNR: 90 dB (typical)

SINAD: 89.5 dB (typical)

SFDR: -105 dB (typical)

INL: ±1 LSB (typical)

DNL: ±0.5 LSB (typical)

Operating power consumption: 350 mW (internal reference)

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

Product dimensions, pins, functions, and timing are compatible for replacement of the ADS8568

Single 5 V power supply, compatible with ±15 V power supply pins, convenient for applications

Lower bipolar required level error, lower positive and negative full-scale error

Higher channel isolation