AN-0992: Active Filter Evaluation Board for Differential Amplifiers

by John Ardizzoni Download PDF

The EVAL-FLTR-DF-1RZ active filter evaluation board is designed to work with the Analog Devices, Inc., differential amplifiers. The filter board enables quick prototyping of two- or three-pole multiple feedback active filters. The board schematic shown in Figure 1 is for a low-pass filter. Converting the board from a low-pass filter to a high-pass filter is accomplished by swapping the location of the filters resistors and capacitors.

Figure 1. Active Filter Evaluation Board Schematic.

Figure 1. Active Filter Evaluation Board Schematic.

The boards also have provisions for edge-mounted SMA connectors, which simplify testing and integration. The input of the filter can be driven either single-ended or differentially.

The active filter evaluation boards are bare, which enables users to customize the filter design. The filter board assembly drawing is shown in Figure 2. All components are 0603 case sizes with the exception of the large bypass capacitors, which are 3216 case sizes.

Figure 2. Active Filter Evaluation Board Assembly Drawing.

Figure 2. Active Filter Evaluation Board Assembly Drawing.

Author

John Ardizzoni

John Ardizzoni

John started at Analog Devices in 2002, as an Application Engineer in the High Speed Amplifier group. Prior to joining Analog Devices John worked for IBM, in RFIC applications and at M/A-COM for 20 years. John is also co-author of Analog Devices Rarely Asked Questions (RAQ's) column. John has over 30 years experience in the electronics industry, and has authored numerous articles and design ideas.