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Channel switching
#3
Hi Guys

There are pros and cons for every switching element.

Jfets are inexpensive, require no power to be on or off, and come in a wide variety of capability. For switching, you want low on-resistance and suitable voltage rating for the circuit point. Using them as shunt switches is simple but as series switches they require a bipolar supply, which you may find easy or difficult to employ. The gate control voltage is not 100% isolated from the channel, so a small amount of care must be taken in the placement of parts.

Relays require a bit of power to energise and this current has to come from somewhere. Supplying the coil is usually the biggest hurdle in using relays. otherwise, relays provide negligible on-resistance and near-infinite isolation between poles and to the coil, so the coil control circuit can be at any voltage, as can be the contacts. Relays cost a lot more than jfets regardless of what deals you might come across. The contacts can be configured for series or shunt switching with no effort at all.

Have fun
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Messages In This Thread
Channel switching - by K O'Connor - 08-22-2018, 04:22 PM
RE: Channel switching - by jmcd - 09-14-2018, 01:05 PM
RE: Channel switching - by K O'Connor - 09-17-2018, 10:22 PM
RE: Channel switching - by jmcd - 11-19-2018, 02:55 AM
RE: Channel switching - by K O'Connor - 11-19-2018, 11:44 AM
RE: Channel switching - by jmcd - 11-19-2018, 02:45 PM
RE: Channel switching - by K O'Connor - 01-02-2019, 02:49 PM
RE: Channel switching - by Champ81 - 08-05-2023, 04:29 PM
RE: Channel switching - by makinrose - 08-06-2023, 11:47 AM
RE: Channel switching - by Champ81 - 08-07-2023, 02:40 PM
RE: Channel switching - by K O'Connor - 08-08-2023, 11:46 AM

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