IF Digitizing Subsystem
The AD9864 is a general-purpose IF subsystem that digitizes a low level, 10 MHz to 300 MHz IF input with a signal bandwidth ranging from 6.8 kHz to 270 kHz. The signal chain of the AD9864 consists of a low noise amplifier (LNA), a mixer, a band-pass Σ-∆ analog-to-digital converter (ADC), and a decimation filter with programmable decimation factor. An automatic gain control (AGC) circuit gives the AD9864 12 dB of continuous gain adjustment. Auxiliary blocks include both clock and local oscillator (LO) synthesizers.
The high dynamic range of the AD9864 and inherent antialiasing provided by the band-pass Σ-∆ converter allow the device to cope with blocking signals up to 95 dB stronger than the desired signal. This attribute often reduces the cost of a radio by reducing IF filtering requirements. Also, it enables multimode radios of varying channel bandwidths, allowing the IF filter to be specified for the largest channel bandwidth.
The SPI port programs numerous parameters of the AD9864, allowing the device to be optimized for any given application. Programmable parameters include synthesizer divide ratios, AGC attenuation and attack/decay time, received signal strength level, decimation factor, output data format, 16 dB attenuator, and the selected bias currents.
The AD9864 is available in a 48-lead LFCSP package and operates from a single 2.7 V to 3.6 V supply. The total power consumption is typically 56 mW and a power-down mode is provided via serial interfacing.
- Multimode narrow-band radio products
- Analog/digital UHF/VHF FDMA receivers
- TETRA, APCO25, GSM/EDGE
- Portable and mobile radio products
- SATCOM terminals
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
The AD9864/AD9874-EBZ evaluation board and its accompanying software provide a simple means to evaluate this highly integrated IC. The AD9864 and AD9874 are general-purpose IF subsystem that digitizes a low level 10 MHz–300 MHz IF input with signal bandwidths ranging from 6.8 kHz to 270 kHz. The AD9864/AD9874-EBZ is a flexible design that allows the user to configure it for different potential applications. In the IF input signal path, component pads are available to implement different IF impedance matching networks. The LO and CLK signals can be externally applied or internally derived from on-board VCO circuits . The reference for the on-chip LO and CLK synthesizers can be applied via the external FREF input or an on-board 26 MHz crystal oscillator (XO).
The evaluation board is designed to interface to Analog Devices high speed converter evaluation platform (HSC-ADC-EVALCZ) for data capture and control but can easily be interfaced to other FPGA, DSP or micro-controller development platforms via its general purpose connector. A simple software SPI control GUI provides an easy means of configuring the AD9864/AD9874. Analog Devices VisualAnalog software is used for real time data analysis.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.