14-Bit, 500 MSPS LVDS, Dual Analog-to-Digital Converter

The AD9684 is a dual, 14-bit, 500 MSPS ADC. The device has an on-chip buffer and a sample-and-hold circuit designed for low power, small size, and ease of use. This product is designed for sampling wide bandwidth analog signals. The AD9684 is optimized for wide input bandwidth, a high sampling rate, excellent linearity, and low power in a small package.

The dual ADC cores feature a multistage, differential pipelined architecture with integrated output error correction logic. Each ADC features wide bandwidth buffered inputs, supporting a variety of user selectable input ranges. An integrated voltage reference eases design considerations. Each ADC data output is internally connected to an optional decimate by 2 block.

The analog input and clock signals are differential inputs. Each ADC data output is internally connected to two digital downconverters (DDCs). Each DDC consists of four cascaded signal processing stages: a 12-bit frequency translator (NCO), and three half-band decimation filters supporting a divide by factor of two, four, and eight.

Applications

* Communications

* Diversity multi-band, multi-mode digital receivers

3G/4G, TD-SCDMA, WCDMA, MC-GSM, LTE

* General-purpose software radios

* Ultrawideband satellite receiver

* Instrumentation (spectrum analyzers, network analyzers, integrated RF test solutions)

* Radar

* Digital oscilloscopes

* High speed data acquisition systems

* DOCSIS CMTS upstream receive paths

* HFC digital reverse path receivers

* LVDS digital outputs

* 1.1 W total power per channel at 500MSPS (default settings)

* SFDR = 85 dBc at 170MHz fIN (500MSPS)

* SNR = 68.6 dBFS at 170MHz fIN (500MSPS)

* ENOB = 10.9 bits at 170 MHz fIN

* DNL = ±0.5 LSB

* INL = ±2.5 LSB

* Noise Density = -153 dBFS/Hz at 500 MSPS

* 1.25V, 2.50 V and 3.3V supply operation

* No missing codes

* Internal analog-to-digital converter (ADC) voltage reference

* See data sheet for additional features