ADMV8818 Digitally Tunable Filter

Product Highlights > ADMV8818 Digitally Tunable Filter

            ADMV8818 Digitally Tunable Filter
                    Analog Devices' ADMV8818 digitally tunable filter has HPFs and LPFs that span the 2 GHz to 18 GHz frequency range
    

ADI's ADMV8818 is a fully monolithic microwave integrated circuit (MMIC) that features a digitally selectable operating frequency. The device features four independently controlled high-pass filters (HPFs) and four independently controlled low-pass filters (LPFs) that span the 2 GHz to 18 GHz frequency range. The chip can be programmed using a 4-wire serial port interface (SPI). The SDP-S controller allows the user to interface with the ADMV8818 SPI through Analog Devices’ Analysis | Control | Evaluation (ACE) software.

The flexible architecture of the ADMV8818 allows the 3 dB cutoff frequency (f3dB) of the high-pass and low-pass filters to be controlled independently to generate up to 4 GHz of bandwidth. The digital logic control on each filter is 4-bits wide (16 states) and controls the on-chip reactive elements to adjust the f3dB. The typical insertion loss is 9 dB and the wideband rejection is 35 dB, which is ideally suited for minimizing system harmonics.

This tunable filter can be used as a smaller alternative to large switched filter banks and cavity tuned filters. This device provides a dynamically adjustable solution in advanced communications applications.

ADI's ADMV8818-EVALZ is available for evaluating the ADMV8818 digitally tunable high-pass and low-pass filter. The ADMV8818-EVALZ incorporates the ADMV8818 chip, as well as a negative voltage generator, low dropout (LDO) regulators, and an interface to the EVAL-SDP-CS1Z (SDP-S) system demonstration platform (SDP) to allow simple and efficient evaluation. The negative voltage generator and LDO regulators allow the ADMV8818 to be powered by either the 5 V USB supply voltage from the PC via the SDP-S or by using two external power supplies.

The ADMV8818 data sheet must be consulted in conjunction with the user guide when using the ADMV8818-EVALZ.

Block Diagrams and Graphs

Insertion Loss vs. RF Frequency at 4GHz Constant Bandwidth - Click to Enlarge

Image of Insertion Loss vs. RF Frequency at 4GHz Constant Bandwidth and Various Temperatures

Insertion Loss vs. RF Frequency at 4GHz Constant Bandwidth and Various Temperatures - Click to Enlarge

Insertion Loss vs. RF Frequency for Board Loss and Bypass Configuration - Click to Enlarge

Image of Insertion Loss vs. RF Frequency for Board Loss and Bypass Configuration

Functional Block Diagram - Click to Enlarge

Features

Digitally tunable multi-octave tuning
Independent 3 dB frequency controls for up to 4 GHz of bandwidth
Digital switched capacitors improve filter linearity and frequency response compared to varactor-based solutions
Single-chip replacement for discrete solutions

Applications

Aerospace and defense: electronic warfare and wideband receivers
Instrumentation: front-end, IF, and anti-aliasing filtering
General purpose: applications that require flexible architecture and compact form factor