The domestically produced 4-channel 14-bit 250MSPS analog-to-digital converter GX4449, compatible with the ADS4449, is applied in smart antenna arrays

The beamforming, spatial diversity, and interference suppression capabilities of smart antenna arrays enhance signal transmission efficiency and anti-interference performance. These functions primarily involve the coordinated reception of spatial signals by multiple antenna elements, followed by signal conditioning, analog-to-digital conversion, and transmission to the baseband processing unit. During this process, the multi-channel synchronization accuracy, sampling rate, quantization precision, and anti-interference capability of the analog-to-digital converter impact the beamforming accuracy, signal resolution, and real-time response speed of the smart antenna array.

The 14-bit high-linearity four-channel 14-bit 250MSPS analog-to-digital converter GX4449 is highly suitable for smart antenna systems. Each channel of the GX4449 employs a multi-stage differential pipelined architecture with integrated output error correction logic. Each ADC features high bandwidth and supports multiple user-selectable input ranges. The GX4449 incorporates duty cycle correction circuitry to stabilize the duty cycle of internal clock signals, ensuring consistent outstanding conversion performance. ADC conversion data is directly output via two pairs of cross-connected, multi-channel multiplexed 14-bit LVDS-level interface circuits.

Product Advantages of GX4449:

Compatible with reference model ADS4449

Four-channel 250MSPS

Low power consumption, no need for a heat sink

ADC built-in clock duty cycle stabilizer (DCS)

Internal reference voltage source of ADC

Single power supply of 1.8V

Programmable Analog Input Range

Programmable amplitude LVDS output

Peak voltage input range; 1.4Vpp to 2.0Vpp, Type: 1.75Vpp

Supports 1.8V or 3.3V serial four-wire SPI interface control

Flexible energy-saving power-off mode

The package adopts a plastic-sealed BGA144, with an operating temperature range of -55°C to +125°C.

Static Performance: DNL: D0.75/+0.75LSB, INL: 04.0/+4.0LSB

Differential analog input bandwidth: 400MHz

Dynamic performance:

-fin=90MHz，ENOB=11.4Bit，SNDR=70.3dBFS，SNR=70.6dBFS

-fin=140MHz，ENOB=11.2Bit，SNDR=69.1dBFS，SNR=69.5dBFS

-fin=220MHz，ENOB=11.2Bit，SNDR=69.2dBFS，SNR=69.4dBFS

-fin=350MHz，ENOB=10.6Bit，SNDR=65.8dBFS，SNR=66.1dBFS

The GX4449 can be flexibly configured into power-down mode based on application requirements, significantly reducing power consumption. The programming for configuration and control is accomplished via a four-wire SPI serial interface.