3v step down from 12v

[Crafts4Me]

hi
my adaptor is 3amps which i believ should be sufficient
the bubbler is 5v 1A-1w
i have about 15 mini Led light
a 12v mini motor maybe 30ma

 

[Martaine2005]

Then your adapter will be fine.
You will still need a 12V DC input to a 5V DC output for the bubbler.
Any of the bottom three links will work and so will the car adapter that @Harald Kapp linked to because it already has a USB connector.

 

[Crafts4Me]

o this on will work alos?
usb female port i think its the first choice

https://he.aliexpress.com/item/1005010616445313.html?spm=a2g0o.productlist.main.28.343c13e2WAOVrY&algo_pvid=f6c523b7-e7ba-4cca-ad95-995bc84ccff7&algo_exp_id=f6c523b7-e7ba-4cca-ad95-995bc84ccff7-34&pdp_ext_f=%7B%22order%22%3A%22-1%22%2C%22eval%22%3A%221%22%2C%22fromPage%22%3A%22search%22%7D&pdp_npi=6%40dis%21USD%212.13%212.13%21%21%2114.81%2114.81%21%4021015b7d17669966444535426e07c7%2112000052982245710%21sea%21IL%21133542592%21X%211%210%21n_tag%3A-29919%3Bd%3A766c82f3%3Bm03_new_user%3A-29895&curPageLogUid=upocXNdvKJGf&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005010616445313%7C_p_origin_prod%3A

then i connect red and black appropriately and connect the USB tot he female port?

is my adaptor sufficient at 3W?

 

[Martaine2005]

With the values you have quoted, a 3A adapter will be fine.
It’s not the maximum current (Amps) that the adapter can supply. It’s the consumption of Amps that the connected bubbler and other electronics require (consume) that is important.
So adding them up is important to make sure that the adapter is appropriate or strong enough.

 

[Harald Kapp]

As you are seemingly struggling somehow with the concept of converting the 12 V to a 5 V USB interface, may I suggest a different venue:

Use a mains extension cord with at least 2 (or more) mains sockets and possibly an on-off switch. Plug the 12 V power supply that you showed in post #79 into one of the mains sockets of the extension cord.
Use an off-the-shelf USB power supply such as this one or any similar product, plug it into a free outlet of the extension cord and power your USB gadgets from this USB power supply. No fiddling with 12 V to 5 V converters.
Plus when you use an extension cord with switch, all gadgets come on and off by simply switching the mains.
Plus these "components" should be readily available at local stores. No need to wait for delivery from oveseas.