Hello,
I have a switch OLED that has some odd issues that I’ve tracked down to a bad voltage regulator for the left joycon. This part is marked 4N8 with pin 1 taking 1.8V, pin 2 taking 5V and pin 4 outputting 4.75V with current draw only 45mA. These values are taken from a known good working switch OLED. Most of the marking ID sites have voltage regulators that output 3.95V.
Anybody have a part number for this component or equivalent? I’ll even take an aliexpress link.
Thanks!
Picture of the offending little bugger. It outputs 0V and I believe is causing a 111 ohm short to ground on this power rail.
I’ve tried to look up the part, but have come up with nothing. Are you sure this component is the culprit? Have you removed it and checked for a short? It’s very possible it’s not putting out voltage due to another part before it that is shorted.
The only other thing on that line that I’m aware of is another identical voltage regulator for the other joycon rail. That one is does work charging the other joycon.
That large cap behind it is going right to it as well, though. It could be a cap or even a diode causing the short before it ever gets to that component. Every component on that line will show shorted until you remove the true short. The only way to tell is remove the VR and check and see if the short is still there. Otherwise, you could be going down a rabbit hole hunting down a component that may not be the problem.
Something else to keep in mind are low impedance lines. Not sure if this has that or not.
To provide a little backstory, this switch came to me with a dead charge port fuse. After replacing the fuse the switch charged and booted but stopped charging after about 10 minutes. Found the MAX8969 labelled ALJ on the far west side of the board smoking hot with a 2 ohm short on the output rail it generates. Replaced the chip and now the switch seemingly charges, boots and runs normally aside from the right joycon rail not charging and the 111 ohm short on the rail coming out of that MAX8969. The only two major components I found on that line were the two voltage regulators, one for each joycon.
That big cap is on the output side of the voltage regulator and the short is not present on that side. No diodes either that I’m aware of. It’s a very simple circuit.
Got it. Good luck in your adventure.
I appreciate the help! I might just wing it and order a regulator that matches what I know. Worse case scenario I kill a joycon I think.
This was a fun search since this pinout isn’t standardized. Finding a VR with enable on pin 1, input on pin 3 and output on pin 4 was a challenge but I think the MAX8868EUK50T fits. Almost all of the other VRs I found had input on pin 1, enable on pin 3, output on pin 5.
Just got the VRs in the mail and they are way too big. I thought I had the package size down but apparently not. The search continues.
Got it. The Toshiba TCR2EE48,LM is the exact part. Even the marking is the same according to the datasheet.
How did you manage to find it? I tried looking for it, but couldn’t find squat.
Anyway, good work.
I took some actual measurements of the failed VR and matched them to the SOT553-5 package. Searched mouser for SOT553 voltage regulators that output fixed 4.5-5V and looked through each results datasheet to match the pinout to what I knew. There was only one matching result and it happened to be correct.
I guess it’s working as I get 4.8V out of both VRs now and the 111ohm short is gone. Fan is now dead though lol. There’s no winning. Also, thanks nintendo for making the switch, switch lite and switch oled all have different fans. I really appreciate it.
