In my case, D4 seems not to conduct current at all. My diode test (DMM, applies 2.5V open voltage) does not show any diode voltage, regardless the direction. Perhaps, it's a bidirectional zener device with over 2.5V threshold in both directions.
The diode however is soldered, but it is a bit side tilted. What type should I use as replacement - if the diode is defect (abnormally not as short).
Rob
On Thu, 27 Feb 2025 19:52:50 +0100, Alejandro Zaragoza via groups.io <pypy1am@...> wrote:
One more detail, I made a jump on U22, it didn't work, but I made some measurements on the passive components around U22 and verified that Diode D4 is showing a short, I'll try to lift it to confirm. The other end of D4 doesn't go to ground. I tried to find the TinySA ULTRA electrical schematic, without success. Where can I get the TinySA ULTRA schematic?
