GXSC Analog-to-Digital Converter Replacement AD9268 for Real-Time Current/Voltage Monitoring in Servo Systems

The servo system enables the output quantities such as position, orientation, and state of an object to follow any changes in the input target. Its primary function is to amplify, transform, and regulate power based on control commands, ensuring flexible and convenient control of torque, speed, and position from the drive device. As a core unit for achieving high-precision position, speed, and torque control, it is widely used in advanced manufacturing fields such as CNC machine tools, industrial robots, and aerospace equipment.

The control accuracy and dynamic response capability of a servo system rely on the real-time and precise monitoring of key motor operating parameters, particularly current and voltage. As the pivotal component in the monitoring link for converting analog signals to digital signals, the analog-to-digital converter (ADC) directly determines the timeliness and reliability of monitoring data through its sampling rate, resolution, and linearity. The dual-channel 16-bit 125MSPS ADC of GXSC perfectly meets the stringent requirements of current/voltage monitoring in servo systems and can be pin-to-pin compatible with the AD9268 for use in servo systems.

The GXSC analog-to-digital converter employs a multi-stage differential pipelined architecture for each channel‘s ADC core, incorporating output error correction logic. In terms of multi-channel and dynamic performance, this domestic ADC features dual-channel differential input ports, supporting full-channel synchronous sampling. It can simultaneously capture three-phase stator currents of servo motors and DC bus voltage, ensuring temporal consistency in parameter acquisition. This serves as a critical prerequisite for precise calculations in advanced algorithms such as vector control and torque feedforward control in servo systems.

All GXSC analog-to-digital converters feature broadband width, differential sample-and-hold analog input amplifiers, and support user-selectable input ranges. The output data can be directly sent to two external 16-bit output ports, which can be configured as 1.8V CMOS or LVDS. When needed, flexible power-down options significantly reduce power consumption. Configuration and control programming are accomplished via a three-wire SPI-compatible serial interface.

The advantages of the GXSC analog-to-digital converter are as follows:

The package adopts a plastic LFCSP64, with functional compatibility to the reference model AD9268

Low power consumption, no need for a heatsink

Optional intra-chip disturbance

Programmable ADC Internal Reference Voltage Source

Single 1.8V power supply

Flexible analog input range: 1Vpp to 2Vpp

Flexible energy-saving power-off mode

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

Differential analog input bandwidth: 650MHz

In addition, the GXSC analog-to-digital converter offers product series with different speed tiers of 60M/80M/105M/125M to meet various application requirements, enabling flexible power consumption control. The speed tier can be identified via the speed level register.