|UPDATE: iFlash iPod CompactFlash adaptor has been launched. More information can be found here.|
I got into the IPod phenomena very late well actually only a few months back. Everyone around me had these ever so wonderful gadgets and they loved talking about their new found
Did I feel jealous hell no, I have programmed myself to follow the ultimate contrarian life – if it is popular and everyone around me likes it I will always find several reasons why I don’t. With Apple the reasons were pretty clear, I don’t like propriety technology and I don’t like popularity!!! So a few months back I heard these evil words from my wife – why don’t you get me an IPod, before I went in to a rage of rants I decided ok I will.
Being a cheap skate and also having the self believe that I can fix anything, I decided to start my purchasing search in EBay’s faulty and broken categories. While I was searching I noticed that 80 to 90% of faulty video IPod’s seem to suffer from dud hard drives, so popular in fact that it has been coined the ‘click of death’.
Let me remove the wife element of this tutorial – she got her video IPod lovingly restored by yours truly and she is living happily ever after with it!
So after spending several hours playing with the video IPod and I could feel my hatred for this iconic symbol waning and I did not even have to use their propriety ITunes as someone was good enough to write an excellent Winamp plug-in. However every sound coming from the miniature hard drive working away inside reminded me about the click of death, which is when I decided to find a solution to remove the mechanics from the equation.
I decided the best solution would be to replace hard drive with a solid state alternative in the form of a compact flash card. Various searches later had showed me lots of people had been successful in replacing the HDD in older IPod’s but not the 5th gen video IPod’s, these people should also be put forward for some sort of prize with their amazing hand soldering skills working on 50 way 1.27mm pitch connectors. So no one had cracked the video IPod and this is because of the new fangled connector found on the hard drive, it is zero insertion force (ZIF) type 40 way connector which uses an eye watering 0.5mm pitch.
The installed hard drive is manufactured by Toshiba and a quick search of their website turned up the user manual for the said MK3008GAL drive, thankfully the connector may be different but the signals carried are the same old ATA type. So theoretically it should be no problem interfacing it to a compact flash card.
So after a few hours measuring and prodding with my oscilloscope and going through several pdf’s from SanDisk and Toshiba – finally I came up with a circuit which I felt would do the trick. So now I was left with tracking down the relevant connectors to mate to the IPod and to the compact flash card.
Internally the IPod is extremely well packed and it was pretty much a necessity that my circuit and all its extra’s had to fit in the same form factor as the hard drive I was replacing. The hard drive measures 5mm x 54mm x 71mm, a compact flash card only measures 4mm x 43mm x 36mm so no problem there. Compact flash connectors are pretty much standard things and most measure 47mm wide, once again no problem.
In fact the only place I could see a problem was in the height most CF connectors are 4.5mm and need to be mounted on to circuit board which is going to be 1.6mm in my case. The IPod side was going to be the least to worry about in terms of sizing – the connector is ultra small. After spending lots of time flicking though parts catalogues I settled on the connectors, 3M supplied the low profile CF connector (4mm height) and Hirose the 40way 0.5mm ZIF flip-lock connector.
Now I could finalise the circuit board design and get the PCB made. My final design would measure with the Compact Flash card inserted 5.6mm x 51mm x 61mm, great!! Form factor smaller than the hard drive, slightly thicker but that should not matter as I will not be using the rubber mounts that hold the drive.
The PCB finally arrived and the very hard task of mounting the connectors began, these things are designed to be soldered by exotic techniques such as solder reflow and wave ovens – sadly I don’t have luxuries like that so with my trusty hot air soldering station and some solder paste I set to work!!!
Eureka moment came and went very quickly, after perfectly mounting and soldering the connectors I discovered some errors in how I had routed the tracks – normally at this tiny scale I would have ditched the PCB and ordered new ones, but I was so eager to see if this would work I set about correcting the errors using a magnifying glass and some conductive paint to bond wires (note to self: don’t try this again!).
As you can see from the images I applied some self adhesive neoprene to the bottom of my circuit board and along the top of the CF connector, these will hold the interface tight when the case is closed. click on images for larger versions.
So the circuit was ready for testing, I won’t bore you with how to open the video IPod several websites already do that and they probably do a better job than I ever could (they can be found here and here.). So I removed the hard drive by lifting the flip lock so the ribbon cable slides out of the connector. I inserted a 4 GB CF card to my module then carefully bought it up to the iPod ribbon cable, sliding slowly in to the ZIF connector once it was home I pushed the flip lock down.