Hi, I've got an Analog Devices LTSPICE VII simulation of a bandpass filter based upon "Typical Application" on page 1 of the LTC1060 (https://www.analog.com/en/products/ltc1060.html#product-overview) datasheet, and my simulation with the sample values from Example 1 - Design
closely matches the performance shown in Figure 1 4th Order Butterworth BP Filter, f_0PB = 2 kHz
shown in the corresponding Linear Technology Application Note AN27A-1.
My goal is to use the same op-amp strategy dual-stage 4th (or higher) bandpass filter with a target design center frequency of 455 kHz, and the target desired bandpass region of the 2nd stage:
- Selectivity (-6/-60 dB) SSB/CW: 2.2 kHz/4.5 kHz
- target filter is 300 Hz/1.0 kHz or 500 Hz/2.0 kHz
Is the LTC1060A device the suitable choice for this application?
ex. f_0BP = 455 kHz, BW = 300 Hz so f_0BP/BW = 1516 @ 300 Hz BP, or 910 @ 500 Hz BP.
What could I do to design such a filter using ADI products? This is to replace an unobtanium mechanical filter originally made by Collins. The shape of the filter actually matches the AN27A-1 Figure 1, hence my interest in LTC1060, but if there is a more appropriate device, which one should I focus on?
Thanks.