Silicon 3V3 DPDT Alternative?

I have multiple sets of jumpers to route UARTs and other lines depending on which of two microcontrollers I'm programming on a board.

I'd like a way to set jumpers with a single control signal.

Most (probably all) of the jumpers route a 3.3V signal from one device to another.

I don't think any of the signals are bidirectional.

My application is similar to wanting to be able to select which of two Propeller chips to program with a Prop Plug. By setting a single pin high or low, I'd like to be able to route all the Prop Plug connections to one of two possible chips. This isn't the exact application I have in mind but I think it describes the problem reasonably well.

I'm wondering if a multichannel buffer could be used this way. I'd need a buffer which had an enable pin. I could use an inverter to enable one buffer chip while disabling the other.

Can anyone suggest appropriate chips for this type of application? I'm not certain how many lines I need to switch but it's likely around four.

Comments

  • jmgjmg Posts: 14,372
    Duane Degn wrote: »
    Silicon 3V3 DPDT Alternative?

    Depends how distributed you want it.
    Popular and cheap is xx3157 single gate SPDT parts, that you sprinkle on the board. They are bidirectional, which can be a bonus. (can save pullups)

  • jmg wrote: »
    Popular and cheap is xx3157 single gate SPDT parts, that you sprinkle on the board. They are bidirectional, which can be a bonus. (can save pullups)

    Thank you. That helped a lot. Your description helped me find this which helped me find this part.

    QFN_16_t%20-%20Copy.jpg

    It looks like the four pole double throw chip is often used with dual SIM devices.

    The four pole device looks like a better bang for the buck but now that I know about the single pole device, I'll likely find lots of applications for it. The single pole device sure looks easier to solder. I usually use a solder mask for soldering SMT parts but I always like the option of probing leads.

    Thanks again for your help.
  • Would the humble 74LV4053 be of merit?
    3 x SPDT (so your application might need 2)
    Optimized for 3V3 operation.
    Analog, so it can be bi-direction, as needed.
    Adds 100 ohms in series, but maybe not such a big deal for digital i/o?
    Enable pin, in case you do want to disconnect all.
  • Since you know the direction something like a 74LVC125/74LVC126 or 74LVC157 could do the job easily
  • Cluso99 wrote: »
    Since you know the direction something like a 74LVC125/74LVC126 or 74LVC157 could do the job easily

    Those look like the type of devices I had in mind.

    I'm glad to know about the other parts as well.

    Thanks everyone. These replies have helped me a lot.
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