The LTC1564 is a new type of continuous time filter for antialiasing, reconstruction and other band-limiting applications. No other analog components or filter expertise are needed to use it. There is one analog input pin and one analog output pin. The cutoff frequency (f_C) and gain are programmable while the shape of the lowpass response is fixed. A latching digital interface stores f_C and gain settings or it can be bypassed for control directly from the pins. The LTC1564 operates from 2.7V to 10V total (single or split supplies) and comes in a 16-pin surface mount SSOP.

The LTC1564 is a rail-to-rail high resolution 8th-order lowpass filter with two stopband notches, giving approximately 100dB attenuation at 2.5 times the passband cutoff frequency f_C (a de-facto standard for DSP front ends). Signals with low or variable levels can be normalized with the built-in variable gain that reduces input-referred noise with increasing gain for a typical dynamic range (maximum signal level to minimum noise) of 122dB (20 equivalent bits) with 20kHz f_C and 118dB at 100kHz f_C on a ±5V supply.

Other frequency-response shapes can be provided upon request. Please contact Analog Devices Marketing.

Applications

• Antialias or Reconstruction Filtering
• DSP Systems
• Communications Systems
• Scientific Instruments
• High Resolutions (16 Bits to 20 Bits)
• Processing Signals Buried in Noise
• Audio Signal Processing
• Programmable Data Rates
• Automatic Gain Control (AGC)
• Single Part Replacing Multiple Filters

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.