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I am planning a future project, but I need the ability to have a 5V logical high enable a 12 or 24V source from an external supply, in a standard DIP package. I remember using something exactly like this YEARS ago in high school, but I cannot remember the specifics.

Pretty much, the issue is that I am clearly searching for the wrong term when trying to identify it. If I knew what this is CALLED, then I should be able to get all the google results I need.

All I know is that it was a standard DIP, and according to the datasheet, it was capable of allowing an external 24V supply to pass through with a couple amps at least, with the enable condition being a 5V logical high, acting as a sort of "switch" for the 24V. It MIGHT have had multiple in a single package, although I cannot recall.

I have heard that I should look into the TI Power IC, but there seem to be several different families within that category on their website, so I am having an issue narrowing it down further, if that even fits the bill.

Any help on finding this would be greatly appreciated! If you know some part numbers, please answer below - I can take care of the rest.

Here is a very crude diagram, showing the BEHAVIOR (there was no audible switch, I am merely showing what it DID).

enter image description here

chronotides
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  • 1.5A? You're looking at using a MOSFET as a low side switch : just make sure its RDS(on) is specified at Vgs=5V, some need 10V gate drive. –  Dec 16 '20 at 19:27
  • Do you happen to have a particular part number I can use as a starting point? I can find one similar if it doesn't work exactly, but I think this might be it. So yeah, 24V, couple of amps in a type of 5V logical "switch" control. – chronotides Dec 16 '20 at 19:28
  • There are a number of solid state relays (SSR) that will do the trick. They come in a variety of packages. – Math Keeps Me Busy Dec 17 '20 at 05:50
  • Behaviou seems like open collector. You can check simple ULN2003 IC. It is an open collector darlington transistor array.Please check the datasheet for voltage and current limits. https://www.st.com/resource/en/datasheet/uln2001.pdf – ExpinElectronics Dec 17 '20 at 06:10
  • I did some digging, and from what I can tell, the TC4423/24/25 family is what I am looking for - Here is a link to the datasheet for the family from Microchip, the manufacturer (the 4423 has both OUTa and OUTb as inverting, 4424 both non-inverting, the 4425 one of each): link – chronotides Dec 17 '20 at 07:28
  • With respect to that, I would like to make sure I understand the behavior right: You supply some power to the Vdd pin (example: 12V), and then you can enable that 12V output on either channel A or B by supplying TTL 5V to the corresponding IN pin (I plan on using TTL, mostly). Is that the correct behavior, judging from the datasheet? – chronotides Dec 17 '20 at 07:33

1 Answers1

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It is called logic level translator, level shifter.

You can also use MOSFET low-side gate driver that usually input 2-5V and have their high side at 20+V.

For the down conversion, you can simply use a resistor divider.

EDIT

The question isn't very clear as to how much current you want to switch.

If you need to switch a load with a couple of amps based on your schematic, you can simply use a N Channel MOSFET, if you switch at low frequency you can directly drive it from 5V, just make sure the MOSFET Vth is lower than 4V to keep some margin. If the load is inductive, add a flyback diode.

Damien
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