Voltage Regulators and Current

Joined
Oct 3, 2020
Messages
60
Likes
16
Hello all! I hope you are all having a good Easter weekend. I have been having a big issue with the power for the PS2 advanced trim. I currently have 6 voltage regulators (the 12 voltage one is for the screen and driver board and I'm going to decrease that voltage) all in parallel with each other, and with the input to those 6 being 16V(4 li ion 18650 batteries in series connected to a BMS that then goes to parallel with a USB C charger and the voltage regulators input) at 6A. Since the 6 are in parallel the current then drops to 1A Across them.. this leaves me too much current for 1.75 , 2.5 and 3.5 V regs(all need 0.1A) and too little for the 1.25 reg(3.1A) ( I am unsure what I need for the 5 V reg and if I even need 1, the 12 V one I am going to test the driver and see what current is needed for operation) no matter how many times I try and re arrange the batteries or regulators I still run into the issue of unbalanced current. What is the best way i can balance the currI appreciate any help I can get. Here is the schematic for the voltage regs and the type of buck converter im using, of anyone has any questions please feel free to ask.
20220416_134641.jpg
 
Joined
Nov 9, 2017
Messages
678
Likes
595
Location
CA
Portables
8
Wouldn’t it be better to convert lcd to run at lower voltage instead of using 12v.? And then use a 2s bms like in photo to get 8.4v output. For those converters your using you need 3.2v-40v input
AAF6E60A-A06C-49E1-8462-09053ED35CF6.jpeg
 
Joined
Dec 6, 2020
Messages
226
Likes
260
Location
Canada
Portables
3
So really want to throw some info your way to make things easier,

From the trim guide

Voltages
1.25v ~3.1A
1.75v ~0.1A accepts 1.8v
2.5v ~0.1A
3.5v ~0.1A accepts 3.3v

3 of those voltages are extremely low so it's very easy to run those off a linear reg from a closer voltage. On the note of 1.75 (1.8v acceptable) it is very much recommended to use a linear reg for system stability of the current over a switching reg.

Going with a 2s power setup it would be very easy to run a larger 5v reg around the 5a range to run a screen voltage direct 2s battery power or modded (3.3v stepdown or 5v stepdown), as well stepping down 2s to 3.3v (aka 3.5v) would allow driving the necessary low amp powers 1.8v (aka 1.75v) 2.5v with linear regs vs switching. This would leave 3.3v with higher current to run a uamp for audio as well.
 

Stitches

2 and a Half Dollarydoos
Staff member
.
.
Joined
Feb 5, 2017
Messages
3,776
Likes
2,982
Location
Banana Bender Land, Australia
Portables
6
Regulators will only draw as much current from the supply as they need to in order to supply demand, they don't need to be fed their max draw at all times. 16v 6A is way more than enough to run a PS2, hell you could run several off that much juice.

I do have doubts about your regulators tho, those things are pretty shit and have a high failure rate.
 
Last edited:
Joined
Oct 3, 2020
Messages
60
Likes
16
I didn't know Regulators are capable of that. That makes things alot easier. As for the kind of Regulator, i was juggling between using linear or buck converters... what brand do you guys recommend??(kinda upset that the ones I bought are crap)
 
Joined
Apr 12, 2017
Messages
194
Likes
130
Location
Canada
I didn't know Regulators are capable of that. That makes things alot easier. As for the kind of Regulator, i was juggling between using linear or buck converters... what brand do you guys recommend??(kinda upset that the ones I bought are crap)
Hey buddy don't sweat that, if only you knew how many pieces of crap tech I've bought for my projects... Anyway you definitely want to use switching regulators (or buck converters, as they are sometimes known) as they are by far the most efficient, and actually do follow the rule that @Stitches mentioned, about only drawing as much energy as is needed. Linear regulators on the other hand discard the unused energy as useless heat. Definitely go with switching regulators (buck converters) if you can
 
Joined
Oct 3, 2020
Messages
60
Likes
16
Hey buddy don't sweat that, if only you knew how many pieces of crap tech I've bought for my projects... Anyway you definitely want to use switching regulators (or buck converters, as they are sometimes known) as they are by far the most efficient, and actually do follow the rule that @Stitches mentioned, about only drawing as much energy as is needed. Linear regulators on the other hand discard the unused energy as useless heat. Definitely go with switching regulators (buck converters) if you can
That sucks man, I wish that you were able to know which converters were good and which were garbage
 
Joined
Apr 12, 2017
Messages
194
Likes
130
Location
Canada
In general you can't go wrong with anything from Texas Instruments. I believe the PS2 PSM all TI
 
Top