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Does anyone know some ref of high voltage high bandwidth analog multiplexer? I am looking for a mux that can tolerate input voltages up to 10V, but has also a high bandwidth of at least 1Ghz. I am not sure that such component actually exists...

I need a high bandwidth because I want to pass very short pulses, typically between 1 to 10 ns, in the multiplexer.

Follow-up: I just found parts from Analog that look promising: ADG1236 and ADG1213. Both have a 1 GHz bandwidth and can use a power supply of +/-15V. However the bandwidth is given for a load of 50 ohm. Will the bandwidth heavily depend on the load? In that case, what would be the bandwidth for, say, a load of 1 kohm?

Thanks.

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  • \$\begingroup\$ @Oliver - It looks to me like your Analog parts are a better answer than the ones you've been given thus far. You're welcome to post that as an answer, and accept it, if it works for you. However, the 50 ohm vs. 1kohm question probably deserves its own problem entirely. Short answer: Yes, the bandwidth depends heavily on the load. You want everything to match at 50 or 75 ohm, typically. \$\endgroup\$ – Kevin Vermeer Mar 11 '11 at 21:29
  • \$\begingroup\$ Alright, I also posted a separate question regarding the bandwidth vs. load issue: How the bandwidth is impacted by the load? \$\endgroup\$ – OlivierB Mar 11 '11 at 21:51
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How about a relay? I guess it depends on how fast you want to switch and the impedance of what you're switching

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  • \$\begingroup\$ A relay may indeed do it I guess. But as you pointed out, the switching speed is an issue. This would be a serious bottleneck in my design, so I will only consider it if I have really no other choice... \$\endgroup\$ – OlivierB Mar 10 '11 at 21:01
  • \$\begingroup\$ Reed switches (en.wikipedia.org/wiki/Reed_switch) may be especially useful. \$\endgroup\$ – jpc Mar 11 '11 at 11:12
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As usual, I can suggest going for discrete FET's controlled from some shift-registers (if you are limited on pins).

While switch speed might be some 10ns, once it's settled, it's like resister, without much bandwidth limiting.

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  • \$\begingroup\$ But beware of gate capacitance (especially during switching) and package inductance (it's 1GHz after all). \$\endgroup\$ – jpc Mar 11 '11 at 11:05
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The ADG1236 and ADG1213 parts from Analog seem to fulfill the requirements. Both have a 1 GHz bandwidth and can use a power supply of +/-15V. They also offer a much higher switching frequency than a relay.

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How about an optoisolated solid state relay? What switching speed do you need?

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  • \$\begingroup\$ Why would have an optoisolated solid state relay a higher bandwidth than a standard analog switch? Besides, it would certainly have a lower switching speed. \$\endgroup\$ – OlivierB Mar 11 '11 at 16:05
  • \$\begingroup\$ @Olvier - Two reasons: a) usually higher voltage range, b) switching speed is still fairly fast (though not as fast as a discrete FET), c) doesn't require the input to referenced to the control signal (driving a FET could be difficult with a varying signal on the output.) \$\endgroup\$ – Thomas O Mar 11 '11 at 16:14

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