Test Clip for 8 contact VDFN flash memory chip? - Page 1
Forum section: electronics / testgear

author: kyle
author_rank: Contributor
timestamp: October 23, 2017, 03:36:53 am
content: Hello,Can somebody help me out finding clips/grabbers that would work with a "8 contact VDFN" package chip?http://www.bdtic.com/datasheet/EON/EN25QH128.pdfThe flash chip is located on my Thinkpad T430s laptop that I'm trying to reflash stock UEFI firmware via SPI with 100% open source Coreboot firmwarehttps://www.coreboot.org/.The pitch appears to be ~1.2mm or so (measured with crappy ruler and my eyes). I know that Pomona 5250 Test Clip is very popular but that's for SOIC. Would it work with my VDFN?Thanks in advance.

author: ElektroQuark
author_rank: Unknown
timestamp: October 23, 2017, 07:16:49 am
content: For a "one time job" you could solder some wires directly to the solder pads. Somewhat tricky but it will work.

author: voltlog
author_rank: Regular Contributor
timestamp: October 23, 2017, 07:36:35 am
content: It would be next to impossible to fit one of those clips in there due to surrounding passives. The memory chip and it's pads are very close to the board and you will not be able to bring the contacts that close to the board. Soldering some wires would be the best idea in this case. You don't necesarly need to solder on the chip itself, you might find those signals on nearby test pads and/or pull-up resistors. Good luck!

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: October 23, 2017, 07:50:27 am
content: It's only 8 pins - solder some wires on.if you want something more robust, glue a piece of protoboard to the top of the chip with a connector on it, and wire down to the pins

author: texaspyro
author_rank: Super Contributor
timestamp: October 23, 2017, 05:08:28 pm
content: I used a SOIC-8 clip on a similar package. I cut off all the plastic surrounding the pins. It was rather wonky to use, but it worked.

author: kyle
author_rank: Contributor
timestamp: October 24, 2017, 10:28:24 pm
content: Thank you for all the suggestions. I ended up soldering smallest wires I could find and using sharpest bit on the soldering iron, and then I put some hot glue on them to keep them from falling off. It was extremely hard to solder them, this picture isn't doing justice, in real life there's barely any room to work with, but I got it!I finally dumped the 16MB ROM off the flash chip, I used piratebus 3.6 with very old firmware (as I didn't have my beagleboard nor raspi prepared for SPI reading).Code:flashrom -p buspirate_spi:dev=/dev/ttyUSB0 -r t430s_stock.binIt took piratebus 50 minutes. It seems like flashrom can control piratebus on its own, it's pretty cool, all I had to worry about is wiring. Now at the very moment I'm dumping the flash chip again and will compare the hashes.

author: ebclr
author_rank: Super Contributor
timestamp: October 25, 2017, 02:11:22 am
content: May this one will be helpCheck the linkhttps://pt.aliexpress.com/item/TSSOP-MSOP-car-remote-control-key-chip-pin-SMD-DIP-chipIC-clip-clip-burn-folder/32535219524.html?spm=a2g0s.9042311.0.0.by4JMI

author: kyle
author_rank: Contributor
timestamp: October 25, 2017, 06:02:16 am
content: Quote from: ebclr on October 25, 2017, 02:11:22 amThose clips are indeed tiny, might be small enough to work.I flashed the coreboot firmware successfully. Still working on improving my grub2 config, and possibly might recompile coreboot again and modify its config, it is much like configuring and compiling Linux kernel, there's plethora of settings and it never feels like you're done. Coreboot in itself is "only" minimal code for initializing a mainboard, after initialization it jumps to a payload, in my case payload being grub2bye bye CIA/NSA/FBI, no more proprietary/shady 5.0MB mini realtime OS running in Intel ME subsystem.