The LTC1164-5CN#PBF with Active Filters L/P Clk Sweepable Butterworth Filter by Analog Devices is a programmable active low-pass filter designed for high-quality audio systems. It features user-selectable center frequency, clock synchronization, and Butterworth filter order, allowing for simple and effective adjustments to the frequency response of audio systems. The device can provide various filter types including Butterworth, Bessel, and Elliptical, as well as three different passbands: low, medium, and high. It also contains a power supply filter that ensures low noise for sensitive audio signal operation.