Maximize consumption – PCB simplification - ZJ050NA-08C

[Luigid]

Hi everyone, I had this LCD board, and in my spare time, I looked at how the components could be modified to simplify the circuit and reduce both the number and size of the components—all in a simple way:

1. Purple box: replace the old diodes with low-voltage-drop SMD models: TOSHIBA CUS08F30,H3F
2. White box: replace old inductors with higher-performance SMD models: YJYCOIN YNR4026-220M and Coilcraft LPS4018-473MRC
3. Blue box: replace the large capacitor with an SMD one rated at least 10µF 10V.
4. Green box: replace the large original quartz crystal with an SMD version (12.000 MHz).
5. Last but not least, create a bridge between the two center pins of the former IC (as shown in the photo) and short-circuit the pads of the former inductor.
   
   

With this configuration, you can use the original power connector and safely power the screen at 5V.

Power consumption at 5V has dropped to around 340mA—not bad!
Optional (highlighted in yellow): replace the old AMS LDO with a higher-performance DC-DC converter (3.3V output)—for example, using a small module:

Consumption should certainly drop further, but this remains to be tested.
It is hardly worth considering replacing the other AMS on the right side of the board, given that it draws only 15–20 mA.

 

[cy]

Super cool idea! Looking forward to seeing how much you can shrink this down! Would be really cool to work this into AIO projects, but running the screen more efficiently and having a smaller footprint would also be really nice!

 

[Stitches]

That's quite a tangible improvement

 

[Luigid]

Super cool idea! Looking forward to seeing how much you can shrink this down! Would be really cool to work this into AIO projects, but running the screen more efficiently and having a smaller footprint would also be really nice!

Driven by curiosity, I gave it a try using a module I had on hand—it took just a few minutes. It isn't the ideal choice, as it's not a pure DC-DC converter, but we can see another 27mA being saved.

 

[Luigid]

Hi, latest update:
Since I didn’t want to stick with the 802, i was sorting through my stuff and dug up the TLV62095RGTR I’d originally used on my PS2P, so I figured I’d find it a "new home", even though it might not be the best application given the low load. Using a small inductor and stepping the voltage down to 3.1V, boom—5V and 300mA spot on, almost 12% less than the initial value with just a few tweaks.