Question about switching regulators for portables

Joined
May 4, 2019
Messages
32
Likes
32
Location
Rocket City, Alabama
Portables
1
I'm working on a PS2 portable, still designing the case but already purchasing components.

I have a quick question about switching regulators for powering the project. I have found the TI PTH08080 modules on digikey, but I already have several UBECs used for RC vehicles to separate the ESC power from the video TX power. Would it be advisable/possible to use one of the UBECs as a replacement for the PS2 7900X on board regulator?

I want to be able to power a RasPi and the monitor off the same supply and the PTH08080 only puts out 2.25A which isn't quite enough without the RPi giving me undervoltage/undercurrent warnings. Found that out while building a RPi portable using a USB power pack rated to output 2.5A.

One of the UBECs I have is listed below:
https://smile.amazon.com/gp/product/B01MUAGOAP/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1
 

cheese

the tallest memer in town
Staff member
.
.
.
Joined
Mar 2, 2016
Messages
2,716
Likes
2,355
Location
Florida
Yes, but...

You'll want to double check the output voltage, and make sure you aren't overloading your UBEC. As long as it's putting out ~5v and it can provide enough amps, you *should* be good...
 
Joined
May 4, 2019
Messages
32
Likes
32
Location
Rocket City, Alabama
Portables
1
Thanks. Ill verify the current capability, but I can confirm it provides 5V from a 2S pack.

The primary unknowns at this point are the dropout voltage and how much noise it will create during operation. Noise can be countered with some bypass caps and/or an LC filter. If it will still function when the batteries get to 3V per cell then it would be a great replacement for the PTH08080 boards, even though it is slightly more expensive.

I don't currently have an O-scope to measure noise but I'll run some tests and find out the working voltage range to post here.
 

cheese

the tallest memer in town
Staff member
.
.
.
Joined
Mar 2, 2016
Messages
2,716
Likes
2,355
Location
Florida
You shouldn't have to worry much about noise, both the display and pi have regulators onboard that drop the voltage lower, a bypass cap should be enough.
 
Top