Good evening~

Is this photo taken behind a windscreen glass? I really love the feeling of looking through glasses as the view will be slightly tinted.

Completed soldering of my CS4398-REV2 board, looks not bad after cleansing.

腦電感應是不是一種對大腦的、基於電磁輻射洩露的側信道攻擊？

Is brain sensing a type of side-channel attack on the brain, based on electromagnetic radiation?

Capacitive Touch Sensor, Rev.F

@raysky-rt.bsky.social さんのイラストです！
是自己 OC （或者說是自設）的插畫。
An illustration of my OC by RaySky.

Working on my OC...

Yes!

New Board Arrived

Lovely BGA chips

some one screenshotted me when I was streaming
having difficulties with BGA packages.jpg

有人在我直播時截圖了
被 BGA 封裝為難.jpg

It's a common feature for most EDA softwares. Usually, fifferent layers have different default colors, like top layer is red and bottom layer is blue. You can turn of custom net color and they will show in the default colors.

white pupils looks... mysterious, yet very adorable

😘

They are actually net colors~ You can assign colors to nets or net classes in this tab. I would prefer assigning different protocols & power rails with different colors.

WIP
Isn't it strange to use a STM32H7 + HS PHY, with a old DAC chip (CS4398) which is almost as old as me...?

But it's interesting that, CS4398 actually lived 20 years and it's still not discontinued.

Yes, they are feedthrough capacitors. They can efficiently filter out high frequency interferences & spikes.

I haven't used them before... But one member in a group recommended them and I want to give it a try.

Yes! It's TPS63070.

erotic PCB layout

It's KiCAD 9!

WIP
Price of STM32 microcontrollers are rising, the interface chip is twice more expensive than that DAC chip...

Maybe I will use CS43131 later, although it's not challenging as it integrated an HP-AMP which can simplify the design.

3rd order low-pass filter. A simple RC filter followed by a Sallen-key filter. The latter filter is compensated to achieve flat group delay in pass band.

三階低通濾波器，一個簡單 RC 濾波器之後跟著一個 Sallen-key filter. 後者經過補償，可以在通帶中實現平緩的群延遲。

DAWN PRO
They may have better performance, but I can hardly identify the difference between playback devices with my ears.

Test result is slightly better than on board audio, but I suppose the result is limited by the recording device & testing environment, which are quite bad.

Tested my CS4398 DAC (Rev 1), its performace isn't as worse as I expected... Although THD+N is really bad (0.02% @ -5dB, 0.01% or 0.008% @ -10dB)

😈🏹

From the experience on last CS4398 DAC project, I decided to make a new CS4398, with STM32H7 as interface and some second hand OP1612 apmlifiers.

H750 is quite cheap now. It's very fast, plus bunches of peripherals that I may or may not use.

ススーロ

沒活了，找點東西臨摹。這次是小塗真紀。
是聽講座的時候開始摸的，不過沒有怎麼優化線條，所以大概顯得很亂。

原作 Pixiv ID: 126483504