Features

• 4-Bit Digitally Controlled 8th-Order Lowpass Filter
  –f_CUTOFF Adjustable from 10kHz to 150kHz in 10kHz Steps
• 4-Bit Digitally Controlled Programmable Gain Amplifier
  – G = 1 to 16 in 1V/V Steps
• Miniature 16-Pin SSOP Package
• No External Components
• 122dB Total System Dynamic Range
• Rail-to-Rail Input and Output Range
• 2.7V to 10V Operation
• Low Noise Mute Mode
• Low Power Shutdown Mode
• Available in 16-Lead Plastic SSOP Package

Typical Application

Description

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 LTC Marketing.