How do I know what batch my order is with? I placed the order on Jan 25th, but I don’t remember what the page said when I ordered.
I have not received any shipping information, nor have I received anything regarding the Batch 2 options. (I found this thread on another forum.)
So my soldering looks good but it still indicates 5V with latest firmware even I set it to 3.3V. I think I might fry this part and one pin seems missing.
I thought bigger blob of solder will fix it but it didnt. I will try to replace it and fix again with new bridge
Is this part ok? I found it locally. Texas Instruments is doing good parts.
Right?
Also found Microchip MCP6001T-I/OT.
So this: https://ww1.microchip.com/downloads/aemDocuments/documents/MSLD/ProductDocuments/DataSheets/MCP6001-1R-1U-2-4-1-MHz-Low-Power-Op-Amp-DS20001733L.pdf
I mean to replace this op-amp as a whole piece and re-do the fix.
Hi @baldengineer,
That probably means you’re in a later batch. It most likely says in Bus Pirate item in your order confirmation.
The only defective hardware shipped a while ago, the rest was caught before it went out. If you haven’t heard anything, it shouldn’t effect you.
Cheers,
ian
The fix looks good. Does the bridge wire also measure 5volts with a multimeter? Once the op-amp has feedback it should be ok.
The part is 5 pin sot-23, so that middle position should be empty.
MCP6001 is the part I actually prototyped with, but it will not work. The pinout is different.
The TI part links to a voltage regulator for me, but TI does make LMV321s. Basically any LMV321 in SOT-23 size should probably fit, it uses a “classic” op-amp pinout.
I can also mail you one from a donor board, and of course I’ll send a new board when I’m able in a few weeks.
This should work:
https://www.digikey.pl/en/products/detail/texas-instruments/LMV321IDCKT/1510543
Right? Same pinout not sure about other specs
I just checked 5.1V. I fried the op-amp definitely.
That little resistor just above the opamp looks like it could use a hit of solder on the right hand side. Maybe it was disturbed during the repair? I’d try that first.
The part you linked is correct type, but the smaller sot 323 size. This is the correct part I believe:
https://www.digikey.pl/en/products/detail/texas-instruments/LMV321IDBVR/381311
Thanks for specifying. I ordered two op-amps and will try to re-solder the resistor.
Let me know how it goes with the resistor. If that is unsoldered, then you would see the same exact thing as without the bridge on the op-amp (op-amp stuck high).
I got the BP5 today. It’s great! Really nicely packaged too.
Regarding the mods, I removed the old MOSFET with a blob of solder and moving the iron above the part until the blob was able to heat all sides enough for it to just slide away. And then replaced with a larger SOT-23 Si2301 since I already had that.
@shabaz your job looks nice and clean.
Very nice clean looking repair! Everyone’s photos look so clear too, I may need a new phone 
After updating my BP5 to latest firmware, confirmed that I had the stuck 5V reading. Connected the pins with a bit of a through-hole LED leg bent to shape, now seeing the correct voltage on the LCD and UI.
Thanks for sharing! Another good looking fix and a nice photo!
Op-amps are on the way to me they should arrive Friday. And next week I go to local HackerSpace. They have a microscope so I will try to fix it again.
P.S. I corrected the solder on that small resistor on the picture but still 5V
The fix is the same fortunately. The pin over the missing pad just connects to the other pin with the jumper wire.
Yeah now I know. I consulted the schematics and its clear that it isnt connected anywhere underneat the board so new opamp and wire will fix it. Hopefully
The fix was very challenging for me and took quite a while but in the end it worked.
I decided to add a trace unter the opamp package.
The FET part was much harder for me.
I cut the trace between the via and the drain and bridged the unconnected drain pad to the nearby trace. After this, i sealed the origin source pad and put a jumper wire from the via to the source of the FET.
Edit:
This is way more easy and takes only a few minutes.
@db1hdn Great looking fix, thank you for sharing your photos!
Hello, I requested a replacement PCB via a support ticket (>10d ago), but didn’t get any response. Did you receive my request please?
Thanks!
