Electronics > Repair
CH341A Serial Memory Programmer Power Supply Fix
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Ian.M:
Probably.  The Thinkpad T440P has two Serial FLASH chips [ref], a W25Q32FV and a W25Q64FV.  Winbond state both have an operating voltage range from 2.7V to 3.6V, [ref] but buried in the datasheets, you'll also find the requirement that

--- Quote ---Note:
1.VCC voltage during Read can operate across the min and max range but should not exceed ±10% of the programming
(erase/write) voltage.
--- End quote ---
Check your programmer's 3.3V regulator output voltage, while connected to the target.  I suspect its somewhere near 3.2V.  Also check the Thinkpad's 3.3V rail voltage, powered on *WITHOUT* the programmer connected. The datasheets say +/-10% difference (but still within the 2.7V to 3.6V range) is permissible.   I'd want some safety margin, so if the two measured voltages differ by less than 0.17V (slightly over 5%) it will be OK to write the FLASH.
PRSXFENG:
Hello there!

I got one of these today, and I noticed the PCB layout of mine is different compared to the one posted in this forum by jakeisprobably. Also, the YJ text is missing on the back
With that said, it is still sadly 5v powered. I tried to read a chip without modding. Unfortunately I killed some other chips on the bus.

I did the mod and the chip reads fine, but sadly the board (a USB to SATA adapter) is dead :'(

For being a soldering noob, surprisingly didn't end up ripping the pin off
Ian.M:
You didn't rip a pin off because you used thin enough solid wire, as I advised back in reply #55.

All I can say about your soldering without being cruel is: Solder joints are meant to be shiny and have generally concave fillets that 'blend' where they meet the wire, pin or pad, not be grey and blobby.  The latter are signs of a 'dry' (bad) joint, too much solder and either movement while it cooled, not enough heat or a lack of flux, maybe due to carrying* the solder to the joint on the bit so the flux core burnt off before it got there - Always apply the solder to the work, never to the bit (except after wiping it, the bit needs a tiny drop put on it for good heat transfer).

However if it works, best to leave it for now.  I strongly recommend practicing adding mod-wires to scrap boards, and also removing and replacing components on them to improve your skills before you work on anything valuable.  The time to learn is *NOW* so don't wait till you desperately need the skills.   ;)

* Carrying solder on the bit for as short a time as possible is permissible, indeed necessary,  for certain specialist techniques (e.g. drag soldering) but *ALWAYS* with extra electronics grade flux pre-applied to the work.
surfwrite:
How to convert a 1.8v adapter and separate WP and HLD with resistors to VCC to read and write QUAD QE
Will it be possible to save a flash dump, because the adapter's transmitter is one way directional
Does it make sense to remod WP and HLD on  both the ch341a itself and on the 1.8 adapter
Did anyone have pictures of the WP and HLD conversion via resistors on the 1.8v adapter
Thanks to you
free_electron:
what software do people use on this ? i see lots of boards but no seller mentions the software. is there such a thing as a generic spi / i2c software as well ( not just targeting eeproms, but more general where you can rea/write anything or even sniff a bus ?
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