AD8174: bandwidth limitation

Document created by analog-archivist Employee on Feb 23, 2016
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How is the bandwidth of current feedback amplifier(for instance AD8174) be
limited from top?


Three key things to remember about current feedback amplifiers:
The inputs are not symmetrical, CFB amps have one high impedance input
(non-inverting terminal) and one low impedance inputs (inverting terminal)
The bandwidth of a CFB amp is independent of the closed loop gain
The bandwidth is set only by the choice of feedback resistor,

For a good background in CFB amps, check our seminar notes "high speed design

The datasheet of each CFB amp generally contains theory notes on operation and
often a table of standard external resistor values for different gain