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Alien Autopsy: Dissecting a Fijit Friends Sage

Pete Brown - 29 November 2011

Pretty sure this image will creep out the strongest of souls

I have a Fijit friend. There, I said it. I have a toy targeted to 9 year old girls. I have a toy my kids want. I have a toy I'm about to butcher in the name of …er … science.


There. Doesn't she look so innocent and happy? You know, I bought this before they were a "hot toy" for Christmas 2011. If that makes me a hipster, pass the glasses. (And no, I didn't pay the outrageous prices people are asking for them now)

Starting with the Body

The body is made up of a flexible silicone outer shell, an ABS bottom, and a soft foam fat layer.

The body uses those wonderful triangle screws at the bottom. I you don't have a compatible screwdriver already, order this ASD3T one from Amazon.


Remove those four screws and also the two holding the battery cover, and the bottom will just pop off.


On four sides, the skin is held to the bottom using simple pegs. The sides use either two or three of the pegs to attach to the bottom. And yes, now I see that this green color is not in the sweet spot for my camera. Sorry about that.


Peel that up, and you'll get to the fatty layer.


The foam doesn't fold up the same way as the skin. It has a glue seam you can break if you want, but I didn't want to do that. Instead, I wanted to be able to pull it up over the neck. To do that, I needed to remove the head.

Crack Yer Head

The head has two halves: front and back. Four plastic dowel screw covers on the head are glued in place.




Ok, the first one came out with little trouble. They must have run out of glue for that one. The others were a disaster. I did quite a butcher job on the back of the head. I honestly think it would be easier to drill those out if you want to get inside this wee beasty with a minimum amount of damage. In three out of the four, I had to leave part of the dowel in place, but jam the screwdriver through the hollow center to unscrew the top. This kept the screw captive, but that was ok.


Because this was mine, I only felt a little bad about it. If this is your kid's toy you're dissecting, I'm pretty sure you're going to hell for this.

Steal your Face

I was impressed with how the face is done. It's actually four layers of acrylic with a Fresnel effect for what they want to light up. Around the perimeter of the face is a band of colored SMD LEDs on a flexible ribbon board. The LEDs turn on in certain locations which causes the fresnel acrylic on a particular layer to light up.


The net effect is a nice and colorful face, and even some "winking" motion handled by turning on and off certain colors. It would be interesting to get a few pieces of acrylic on my mill and see if I could duplicate this effect; it makes for a nice way to light up a robot face, albeit with limited expression.

The LEDs don't appear to have any sort of dedicated controller, just some discrete components you'd expect to find with a string of LEDs.


As interesting as the face is, let's look at what's powering it.

Mmmmm Brains

The daughter board is soldered on top of the main board, and appears to be responsible primarily for motion.


The board has a number of test and/or programming points. A few are labeled, but most are not. Fortunately, the plug connectors are all labeled. I'm pretty sure this is the first time I've ever seen "Tummy" silkscreened on a PCB.


The larger chip you can make out on the main board is an SST 39VF020 256x8 2Mbit flash. There's a bunch of gunk on it too. Yuck.

You'd think with that much flash memory, they could have added a few more jokes.


The two 8 pin chips on top are labeled HG7881CP 1114. I'm guessing these are for motor control.



U1 is interesting. Presumably those are pads for testing or maybe the main programming pads?


Looking at that nasty glue, I'm guessing that's the source of the brown gunk. Still can't be sure, though.

Here's the underside of the main board. There's a lot more brown gunk here. Not sure if that gunk is grease, flux, or some residue from the hot glue gun. It's messy and unprofessional in any case. It is interesting that they decided to put components on both sides. I understand that is generally more expensive than single-sided boards. Add to that the amount of hand-soldering also in this board, and it has to have been relatively expensive to manufacture for its size.


That empty spot in the middle with the 6-grid is right under some potted chip on the other side.

On the lower layer, you can see part of a chip labeled PT25Q16BVSNG with a brand name: PON or POIN or something like that. This otherwise helpful site didn't list them, neither did this one. This site, which doesn't seem to be derived from the same data, also failed me. Here's the best photo I could manage:



There's also something potted in epoxy in the center of the main board, under the daughter board. Presumably this is the MPU. I hate it when they do that. I would liked to have known what the board was running.

Back to the Body

I decided I didn't want to take apart the gears and motors in the head and body. There are a number of them in there, but quite honestly, they're not exactly RC servos, although they look pretty close. Looking at the wires, I'm fairly certain a couple of them have encoders, for example.


Speaking of encoders, here's the motor for the head. I'm not sure what that orange thing is, but it looks a bit like an encoder to me. It appears to have the motor power wires going into it, though. Hmmph.



Clearly you can intercept the calls to the motors and LEDs and replace them with whatever external logic you'd like, either replacing the MPU logic or augmenting it. Without knowing what the MPU actually is, I can't see that you can do much directly with it otherwise.

So, when your 10 year old daughter tires of the thing after a week (really, that's about the play value of one), after they've heard the few jokes and tired of the conversation, trade her for it. I wouldn't go out and purchase one just for hacking, though, unless you know how to get into the brains of the thing.

Then again, you could sure make one mean Dancing Santa from the motors and gears in that body :)

posted by Pete Brown on Tuesday, November 29, 2011
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7 comments for “Alien Autopsy: Dissecting a Fijit Friends Sage”

  1. Brandonsays:
    Thank you for explaining how to disassemble the Fijit friend, loved how you showed the names of the chips, embeded controllers, and show the coders on the motors. Quick question, I plan on hacking a Mykeepon but wouldn't mind hacking a fijit friend, would a Arduino board work on a fijit friend?
  2. Petesays:

    An Arduino may work, but it will be quite a bit of effort (but fun effort) to integrate in there. You'd have to figure out how to use the motor controllers and, if you wanted to keep the voice stuff, how (if even possible) to integrate with the on-board main chip.

    You'd need to use one of the smaller arduinos if you want any hope of putting it inside the Fijit. If you plan to tether, you can use pretty much anything.

    Finally, if you use an Arduino, you may need to supply external power as the Fijit runs on 6v. Test and see.

  3. Celinasays:
    Thank you for posting this! Leave it to my 8 year old daughter to wonder what the "guts" look like :P Here's an idea for the future: Working Fijit with no skin! Creepy, but cool! My little one would love it :)
  4. Pete Brownsays:

    I learned because in the 80s, you were thrown into programming the minute you turned on the computer. You had to consciously choose *not* to program.

    I've loved it ever since. I formalized that in college, but most of it was self-taught through hobbies and later, through work.


    Glad I could help! I love that your daughter is curious what it looks like inside. That seems like something to encourage. :)

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