The LTC1062 is a versatile, DC accurate, instrumentation lowpass filter with gain and phase that closely approximate a 5th order Butterworth filter. It uses an external (R, C) to isolate the IC from the input signal DC path, thus providing DC accuracy. It also offers lower noise and anti-aliasing advantages.
The document describes the LTC1062 as a versatile, DC accurate instrumentation lowpass filter with gain and phase characteristics that approximate a 5th order Butterworth filter. It utilizes an external resistor and capacitor to isolate the IC from the input signal's DC path, ensuring high DC accuracy. The architecture involves sensing the output voltage through an internal buffer before applying it to an internal switched-capacitor network.
Key topics covered include tuning the filter by selecting appropriate external R and C values based on the desired cutoff frequency, utilizing either an external clock or the internal oscillator (tunable up to 130kHz), managing single supply operation, and analyzing dynamic range and signal-to-noise ratios. The note also addresses issues such as clock feedthrough and harmonic distortion.
The maximum guaranteed offset voltage over temperature is 20mV.
The clock should be 100 times the desired cutoff frequency.
Yes, the internal oscillator can be used for applications where clock requirements are below 130kHz.