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flexible connection matrix

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OM222O:
I'm designing a very high precision DMM (I know everyone's going to point out that I'm a fool for trying this, but I've made great progress so far and I'm pretty happy with the results) and I need a way to change connections between the modules. for example there is a wide dynamic range shunt (1 ohm to 100Kohm in 6 steps, each being an order of magnitude), the ADC, the probes, etc.

I do not wish to manually change the probe to different positions, or reconfigure stuff by hand (for example change different ranges) for ease of use.

The simple solution would be relays but they're mechanical parts and prone to much earlier breakdown compared to solid state solutions. For somethings like the ADC, analog muxes are an obvious choice, but for things like the probes and the shunt, high currents (a few amps) can be involved so using a mux is out of the question.

N channel fets would be the next best solution but it's not possible to use them everywhere due to high gate voltages required.

Please let me know if there's anything besides relays that can do this reliably.

Zero999:
What do you mean by flexible connection matrix?

Are you talking about an anlalogue multiplexer? What voltage are the signals? Most analogue multiplexters are limited to a maximum voltage of +/15V, with +/-5 being more typical, in the case of the 74HC4051.
http://www.farnell.com/datasheets/2024221.pdf?_ga=2.34285609.966527979.1596465371-2127120132.1578504493&_gac=1.242411062.1596465371.EAIaIQobChMI5vKp8qD_6gIVF-vtCh0-TwHxEAAYAyAAEgKBy_D_BwE

OM222O:
Yes, I would like to multiplex connections, for example, when going from voltage measurement to current measurement, the probe should obviously be switched to a different part of the circuit (voltage requires high impedance and current requires low impedance). The reason for the title was having used FPGAs where you can connect any pin to any point of the circuit you want (connection matrix) and I don't know anything similar.

I'm more limited by the current rather than voltage as this is a precision DMM for low power electronics (aka no mains voltages, 10s of amps, etc).
The chip you recommended for example, has a current rating of only 20mA. That's practically useless for a switching the probe, as it limits the current measurement to 20mA.

Edit: I've looked into how those analog switch ICs work and it seems like they use a P channel and N channel fet , but they require connections to the body of the fet for biasing which I don't think is possible with discrete fets. So far relays look to be the only real option.

razvan784:
Nevermind advising you to not attempt designing your own meter; it's generally a very bad idea to allow software-controlled switching between voltage and current measurement. There are commercial meters that go to great lengths to alert you of a potential misconnection, e.g. probe detected in Amps jack while Volts mode selected. Also, commercial meters have complex, multi-layered protection circuitry built in, that comes with several compromises that you should be aware of. But maybe your application needs none of that - in that case I suggest researching PhotoMOS solid-state relays.

OM222O:
That is exactly why I want software control. when you switch modes, it automatically changes the input, so you can't mess up the jack connection even if you tried to, plus the continence that I mentioned earlier. Also like I said, no high voltages or energies, so it should be fine.

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