AD8009: Rail-to-rail

Document created by analog-archivist Employee on Feb 23, 2016
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I am using the AD 8009 because of its high speed and broadband functions. My
problem is, that output voltage swing is too small with -3.9 to 3.9 V at
bipolar supply. Is there a way to connect two of them maybe in parallel with
perhaps (+10V and 0V ) and (0V and -10V) as power supply  to get an output
swing of -8.9V to + 8.9V  when one of the two ouputs is used as positive, the
other one as negative output to the BNC or N-connector? Or maybe another way
that I just can't think of? Or maybe another OPamp with a higher Output voltage
swing but the same (or close to it)  parametrics?

 

The lack of a rail to rail output is one of the trade-offs of the high speed
AD8009 architecture.

An immediate way of getting increased amplitude is to use two AD8009 amplifiers
to give a differential output, giving immediately a doubling of the signal
amplitude.

Another solution is simply to use a transformer, to increase the voltage swing
(but decreasing the current drive capability)

Most of the high speed op amps run on +/-5V. One device that runs of +/-15 is
the AD811 or AD844. It also gives a good output current level, so you could use
it for driving a transformer.

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