The FiiO E5 was a low-cost but decent performing compact headphone amplifier a few years back. The unit bore a vague resemblance to an iPod Shuffle clip-version, and was relatively compact with integrated rechargeable lithium-polymer battery. Since someone didn’t want theirs, I managed to snag it second hand for cheap, but I never really had that much of a use for it. After a while, the clip broke, the battery wasn’t really lasting and I decided I might as well tear it apart and throw it out. So here’s a few pictures which I took much earlier this year, which I never got the chance to post until now.
The exterior is a nice aluminium curved shell, and the interior unit slides out after some fiddling with the clips and persuasion to break the glue used inside. The PCB sits inside a plastic frame, with its rear littered in test-points which is covered by a self-adhesive layer of plastic. There is a terminal mounted at the bottom, which provides the grounding point to help reduce any RF interference which might be experienced by the unit.
The internal metal has been cleared of paint where the grounding contact would sit, which is necessary to make it effective.
All the magic is on the other side of the frame, where space seems to be very well utilized. The Li-Poly battery can be seen up-front, with the headphone jacks (in/out) being the next highest profile components. There is a mini-B port for charging.
The battery is marked AK402030PL and has a printed capacity of 190mAh.
The main PCB has all its components mounted on the one side, and all of them are surface mount. Quite a few ceramic capacitors, a tantalum, a number of resistors, two LEDs for charging/operation status, three push switches for volume up/down and power, and a slide switch for bass boost. It seems that the unmarked 8-pin IC is the controller that runs the whole unit. The Burr Brown/Ti OPA2338UA dual op-amp is likely to be responsible for buffering the input and doing the bass boost function. Finally, the TPA6130A2 138mW DirectPath Stereo Headphone Amplifier with I2C Volume Control does the actual driving of the output. It seems there’s a 5-pin charge controller/voltage regulator chip for the li-poly cell marked 54b9, although the battery does have its own protection board.
The E5 did indeed contain the promised Texas Instruments solutions in the signal chain, which explains why it was considered to have good performance, but it was made by the Chinese and at a very low price. This was all good for the consumer, as decent performance could be had for cheap, and it seems that the more savvy consumers know to look towards these brands as they develop a positive reputation.