High Speed, Quad Universal Filter Building Block

The LTC1264 consists of four identical, high speed 2nd order switched-capacitor filter building blocks designed for center frequencies up to 250kHz. Each building block, together with three to five resistors, can provide 2nd order functions like lowpass, highpass, bandpass and notch. The center frequency of each 2nd order section is tuned via an external clock. The clock-to-center frequency ratio is internally set to 20:1, but it can be modified via external resistors.

The aliasing performance of the LTC1264 is improved by double-sampling each 2nd order section. Input signal frequencies can reach up to twice the clock frequency before any alias products will be detectable.

For Q ≤ 5 and for TA < 85°C, the maximum center frequency is 160kHz. For Q ≤ 2, the maximum center frequency is 250kHz. Up to 8th order filters can be realized by cascading all four 2nd order sections.

A customized monolithic version of the LTC1264 including internal thin film resistors can be obtained.

Applications

* Digital Communications

* Spread Spectrum Communications

* Spectral Analysis

* Loran Receivers

* Instrumentation

* High Speed, Up to 250kHz Center Frequency

* Four Identical Filters in a 0.3 Inches

* Clock-to-Center Frequency Ratio of 20:1

* Double-Sampling, Improved Aliasing

* Operates from ±2.37V to ±8V Power Supplies

* Customized Version with Internal Resistors Available

* Low Noise

* Low Harmonic Distortion

* Available in 24-Pin DIP and SO Wide Packages