I have a bunch of cheap buck (I think) converters that do 6-20V input and 5V output; and I want to use one powered by a 24V PSU (this is for a 3D printer).
The current draw of the 5V system should be comparatively low, and constant, but the main supply will vary quite a bit in draw. as the regulator can deal with 6-20 volts I wonder if I can 'scale down' or 'clamp' the supplied power via a simple voltage divider?
I know that usually this is a solid 'No' as voltage drop varies according to current draw, but in my case:
- I need only target a range of voltages between 6-20V versus a single stable voltage
- The input to this is a regulated power supply, which should stabilize the voltage (which transitively stabilizes the current, right?), and I expect this should help.
What about some arrangement with Zener diodes? As I look this up mid-post, it seems along the lines of what I am looking for (i.e. something I can throw together with simple passives I am likely to have or can find in scraps): https://en.wikipedia.org/wiki/Zener_diode#Voltage_shifter
But power supplies and analog electronics always surprise me with their subtlety and I don't trust myself enough to know, so would something like the above work, or should I just buy different DC-DC converters and call it a day?
-- new edits as of 2022-12-17 --
Also, I have a bag of these 6-20v -> 5v converters, could I hook two up in series (or otherwise passively arranged) to get effectively 10v per input, but hook their outputs up in parallel?
I will have to dig up the specs on these converters and the power supply, I was more curious if there were generally applicable approaches to this problem given the circumstances (more or less regulated power on each side of the converter).