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I was watching this youtube video EEVblog video on cascading op amps for increased bandwidth , and I was wondering if this can be used for 2-pole filters, including filters that are made up of multiple 2 pole filters?

Most 2-pole active filters are made using a single op amp , so for example if I want to use the standard 1 Mhz GBWP op amp , and I am making a 2-pole filter , that requires a GBWP of more than 1 Mhz, can I just cascade multiple op amps together until I get the required GBWP needed?

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    \$\begingroup\$ "Can you use lower GBWP op amps for a filter requiring a higher GBWP by cascading op amps to get a higher bandwidth?" Yes, if you do it appropriately. \$\endgroup\$
    – Math Keeps Me Busy
    Commented Jan 28, 2021 at 18:40
  • \$\begingroup\$ It may be simpler just to source a higher GBW amplifier though. \$\endgroup\$
    – user16324
    Commented Jan 28, 2021 at 18:46
  • \$\begingroup\$ Not unless you define real specs \$\endgroup\$
    – D.A.S.
    Commented Jan 28, 2021 at 20:14

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With difficulty.

The additional phase shift of the extra opamps can easily compromise stability.

Cascading opamps will not help characteristics such as slew-rate which will limit the large-signal capability.

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