GXSC ADC Replaces AD9694 for X/S-Band Radar Echo Acquisition

X-band radar features short wavelengths and high ranging accuracy, making it suitable for precision tracking and high-precision detection scenarios; S-band radar offers excellent diffraction performance and long detection ranges, and is widely used in medium- to long-range search, meteorological monitoring, and airspace early warning scenarios. Traditional X/S-band radar echo acquisition solutions typically employ single-channel narrowband ADCs or a tiled architecture of multiple single-channel ADCs. This article primarily introduces a GXSC ADC chip tailored for the acquisition of wideband intermediate-frequency (IF) echo signals in X/S-band radar systems. This chip can replace the AD9694, providing a reliable solution for the design and optimization of precision radar echo acquisition systems.

 

The GXSC ADC is a four-channel, high-speed, high-precision ADC specifically designed for high-end applications such as broadband radar, software-defined radio, and signals intelligence. It employs a 14-bit pipelined architecture, with a maximum single-channel sampling rate of 500 MSPS, with a full-power input bandwidth of up to 1.4 GHz. It features built-in high-precision sample-and-hold circuits and on-chip buffers, supports programmable digital down-conversion, and incorporates a JESD204B high-speed serial interface. The chip offers outstanding characteristics including high linearity, low noise, excellent multi-channel synchronization, high integration, and controllable power consumption, fully meeting the requirements of all X/S-band broadband radar echo acquisition scenarios.

 

The GXSC ADC integrates output error correction logic. Each ADC features a wide-bandwidth input and supports various user-selectable input ranges, with both analog inputs and clock signals provided as differential inputs. The data output from this domestically produced ADC is connected via an internal multiplexer to four digital downconverters (DDCs). Each DDC consists of multiple cascaded signal processing stages, including a 48-bit frequency converter (digital controlled oscillator) and up to four half-band decimation filters. Switching between DDC modes can be controlled via SPI programming.

 

GXSC ADC Product Advantages:

1. Package size is compatible with the reference model, supporting in-place replacement of the AD9694

2. Power consumption is approximately 53% of the reference chip, effectively reducing the overall power consumption of the system solution

3. Wider operating temperature range of -55°C to +125°C, providing better environmental adaptability

4. Small package size, effectively reducing system footprint

5. High integration, incorporating digital downconverters and filters, which helps reduce system costs

6. 204B high-speed interface, facilitating user layout and routing