I own a Palm m100 organizer. It is cheap, and it helps to keep things that before floated around my head, organized. The m100 only has 2MB of RAM memory, which means it is always out of memory, especially when loading GPS maps or web site caches.
It can be upgraded to 8MB by replacing the memory chip. It is not a job for the faint of heart, as it involves some pretty nasty SMD soldering, but I decided to do it anyway. What needs to be done is remove the big EEPROM memory chip, and replace it by a larger one. Thank god it is pin compatible In addition, one SMD resitor needs to be removed. Knowing what I know now, I would definitely never do it again…
The 2MB memory chip, a Samsung 028 K4E151612C-TL60, is on the Palm’s circuit board in the top left-hand corner. This chip needs to be removed and replaced by a physically identical chip with the same pin layout but more storage capacity.
It is a multi-pin SMD chip which means that unsoldering it with a regular soldering iron is a tough job. During manufacturing these chips are positioned on the board by a robot, and soldered in a reflow oven. I do not even own a decent soldering station! But I figured that with a little bit of inventiveness and a lot of sweat it should be feasible to do this upgrade myself.
At first I tried a little unsoldering trick I had read about: solder a single copper strand from a piece of cable from the scrap box to a pad on the printed circuit board, slide it under all of the pins, and then heat one pin at a time while pulling the unsoldered end of the wire at a 90 degree angle, so that it passes under the desoldered pin and removes any solder along the way. At least that is the theory. This trick failed because the SMD chip was so small that I couldn’t slide the single strand of wire under the pins… Time to try something different.
When cleverness and subtlety do not pay off, it is time to rough it. I needed a way to heat all the pins one one side of the chip at once so that I could lift it off the board with a jewlers’ screwdriver. I took the protective lid from an old floppy disk, cut and bent it up, and ended up with something that could work. It unsoldered the chip all right, but ripped off a tiny trace from the circuit board at the same time. This is where that single strand of copper wire came in handy
After cleaning off the excess solder from the pads with a piece of solder wick, I carefully positioned the new chip, a Samsung 949 KM416V4104CS-L5, and tacked it to the board by soldering two pins on opposing corners of the chip. I then soldered the rest of the pins one by one. It wasn’t the best solder job, but it should do. There was one more SMD resistor that needed to be removed from the board. I do not remember which one it was, it was close to the cluster of three resistors alongside the memory chip, maybe it will be clear when comparing the picture with your Palm’s circuit board. You can see the strand of copper I used to repare the damaged circuit trace on the bottom of this picture as well.
Then came the moment of thruth as I inserted the batteries and pushed the power button. Nothing. The screen stayed blank. I though I had fried my Palm, and knew from the start that it would be a hit-or-miss mod, no chance of troubleshooting, reparing anything or rolling back to the way it was before. My Palm was toast.
Until I noticed I had inserted one of the batteries in reverse. I quickly fixed this, pushed the Palm button, and there was the Palm logo! I quickly checked the memory stats, and there it was, 7936K. Success!
- Upgrading the Palm m100 to 8MB DRAM
- Palm m100 8Mbyte Upgrade
- Palm Connected Organizer memory upgrades