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Electronics => Beginners => Topic started by: ali6x944 on March 10, 2016, 04:05:45 am

Title: Is it possible? Voltage controlled multiplexer?
Post by: ali6x944 on March 10, 2016, 04:05:45 am
Hi everyone,
Is it possible to make Voltage controlled multiplexer for a switch mode pawer supply to chose its operating trepology?
Title: Re: Is it possible? Voltage controlled multiplexer?
Post by: Alex Trofimov on March 10, 2016, 10:42:15 am
Hi! Basically, it seems possibly, but in most cases it's better to use one proper topology, that serves all the needs.

To give better answer there's more info needed. Between which topologies would you like to switch? Which IC do you use?
Title: Re: Is it possible? Voltage controlled multiplexer?
Post by: tszaboo on March 10, 2016, 11:52:08 am
Make a resistor string, the input is some reference voltage, like a TL431, divide it down to the  with the correct voltage values. Use these voltages with a bunch of comparators. Route the output of the comparator to some logic ICs, and then the output of those to a bunch of analog multiplexer or switch.
Title: Re: Is it possible? Voltage controlled multiplexer?
Post by: matseng on March 10, 2016, 11:56:14 am
Th OP wants to change the topology of the smps, not the voltage. If I remember correctly the high current paths needs to be rearranged for different topologies, and that can't be done with an analog mux, but rather nice fets or realys. But that would probably mess up any nice low-inductance routing on the pcb and cause a low efficiency.

I guess it would probably be easier to build the different topology-smps modules separately and then just switch between the output DC from the modules....
Title: Re: Is it possible? Voltage controlled multiplexer?
Post by: RobK_NL on March 10, 2016, 12:10:26 pm
This type of question is exactly why my sig is what it is ...