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2-GHz 3-input analog switch for DAC - Please help

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Newbie level 6
Jun 4, 2009
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Hi All,
Currently, I am designing a DAC for a high speed SAR ADC. In this DAC, a 2-GHz 3-input analog switch is needed (Please enlarge the below figure for more details).
Unfortunately, I failed to find any paper about switch operating at that frequency or thereabout.
I also tried with IEEE explore but still could not find any relevant documents about this kind of switch.

Could you please let me know some basic documents or papers about high speed multi-input analog switch. Here, the term "high speed" means frequency of control signal of the switch is approximately 2GHz.

Thank you very much.

Few, or no RF switches are going to let you commutate
at 2GHz. They try to isolate RF from the control ports.
But they will pass / block 2GHz (50 ohm system).

An old-school analog switch, forget it.

There are only a few topologies - simple, T, Pi. I think
the simple switch (pass only) may suffice since the
input signals are probably not moving very fast (T is
for HF isolation w/o leakage, Pi for isolation and low
port impedance).

You will want Ron*Cmsb to be << 1/freq or that will
become your settling-time bind for sample rate. You
will want to design for minimum charge injection to
further tamp down settling time.

Beyond that there is nothing special about 2GHz on the
control pins, you either have the intrinsic speed in your
process or you don't. Might just see how fast one inverter
can drive another and still have full rail-rail swing. If that
isn't 2GHz, then you're probably hosed.

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