GXSC ADC Replaces AD9643 in Ultrasound Equipment

Medical ultrasound imaging offers technical advantages such as non-invasiveness, real-time imaging, radiation-free operation, and the ability to perform dynamic detection, making it a core imaging technology for clinical examinations. The quality of ultrasound imaging primarily depends on the accuracy and real-time performance of ultrasound echo signal acquisition. Ultrasound echo signals reflected from human tissue are characterized by weak amplitude, wide dynamic range, high-frequency bandwidth, and strong temporal correlation, requiring an analog-to-digital converter with high sampling rates, high resolution, and strong noise suppression capabilities.

For this application, the recommended data acquisition device is the GXSC dual-channel 14-bit 250 MSPS analog-to-digital converter (ADC). This ADC employs a multi-stage, differential pipelined architecture and integrates output error correction logic. Each ADC features a wide-bandwidth input and supports various user-selectable input ranges. An integrated reference voltage source simplifies the design. A duty cycle stabilizer compensates for fluctuations in the ADC clock duty cycle, ensuring the converter maintains excellent performance.

The GXSC ADC outputs data directly to two external 14-bit LVDS output ports, formatted in either interleaved or channel-multiplexed modes. Flexible shutdown options can significantly reduce power consumption when needed. Configuration and control programming are performed via a three-wire SPI-compatible serial interface.

GXSC ADC Features:

Signal-to-Noise Ratio (SNR): 70.6 dBFS (185 MHz AIN, 250 MSPS)

Spurious-Free Dynamic Range (SFDR): 85 dBc (185 MHz AIN, 250 MSPS)

Input Noise: -151.6 dBFS/Hz (185 MHz, −1 dBFS AIN, 250 MSPS)

Total Power Consumption: 78 mW (250 MSPS)

1.8 V Supply Voltage

LVDS (ANSI-644 Level) Output

1 to 8-stage input clock divider (Maximum Input Frequency 625 MHz)

Sampling Rates up to 250 MSPS

IF Sampling Rates up to 400 MHz

On-chip ADC reference voltage source

Flexible analog input range from 1.4 V p-p to 2.0 V p-p (nominal 1.75 V p-p)

ADC clock duty cycle stabilizer

95 dB channel isolation/crosstalk

Serial port control

Power-saving shutdown mode