MP3 LCD Salvage

I have an old Eclipse TCH828 MP3 Player that I am hoping to salvage the LCD off of to use with my Mega 2560. I know the LCD still works, but the mp3 player itself is broken so I can’t probe the video signals. The LCD starts off with a simple 4 wire resistive touch panel and a 5 wire LCD, but then the LCD connects to a strange FPC (Flexible Printed Circuit). I can try to drive the LCD off just the 5 wires, but then I lose the backlight and I’m not sure how to do that even. Part of the circuit board is hidden inside the lcd, but what I can see I have attached photos of. Can anyone help?

Resistors:
R1: 0.9 ohms (I think, I can’t get a good reading, resistor for the backlight maybe?)
R2: Absent
R3: Absent

Capacitors:
I can’t get any readings on this

Bump Anyone want to help me or atleast point me in the right direction?

I think that this not worth trying, 37 pins so probably about 32 I/O required, 3.3v or even 1.8v required, no digital interface (i2c,SPI ) :(

I have a Mega 2560 so the IO is not a problem But maybe there is some way to power the LCD and backlight and then just use the 5pin (AKKKK) for driving the LCD? It also seems like 4 pins go to the touch panel

Codec: I have a Mega 2560 so the IO is not a problem But maybe there is some way to power the LCD and backlight and then just use the 5pin (AKKKK) for driving the LCD? It also seems like 4 pins go to the touch panel

I wouldn't do it, it's the same kind of LCD panel in a cellphone, it takes a lot of processing power to control one of these, and you need to know what kind of controller that is on the lcd panel to make it work.

The A and KKKK is for the backlight LED's . One anode and 4 cathode connections.

// Per.

I see, its a shame If only I could fix the mp3 and use it to relay the signals As I have a look at the board it looks like the lcd controller is on the main board anyways

As with almost all MP3 players, you have an ARM microprocessor driving the display. The MP3 decoding can be internal to the ARM processor, or a stand alone chip.

Almost all cheap MP3 players use a single-chip solution.

Anyway, what is wrong with the player, what isn't working - maybe we can help you get it working again.

Using the MP3 player to "relay" information from Arduino to the LCD don't seem feasible - the only thing i can come up with is using the MP3 player as a "Wave shield" and use it to play sounds and samples, and control it from the Arduino.

// Per.

I have no idea, I cant see anything physically wrong and I’m not going to spend my time testing 1000+ smd components. The battery did run (almost) all the way down, I removed it to charge it (it wouldn’t charge with the player) I tested the battery and its fine, but even after I reattached the battery the mp3 would not restart

EDIT: Picture attached - Sorry its so bad, my camera is acting up
I haven’t tried solder refluxing yet…

You could always post a high res picture of both sides of the board, maybe something springs to mind what you can check.

What happened when it died exactly ?

// Per.

The mp3 just went black

There are pictures of the other side of the board in the first post, nothing exciting

EDIT: It was skipping for a couple weeks before it died, but I think that was just the preview option and I couldn't figure out how to turn it off

A couple of things to try:

Straighten that crystal on the right, it looks like one of the pins are almost shorting to it's housing.

What happens when you connect USB, does the unit power on, and can the computer see the USB device in "Device manager" ?

When connected to USB, can you measure any voltage at the battery terminals (no battery connected)

I guess this has a mechanical ON/OFF switch on the edge of the PCB, check that for continuity when switched.

A reflow on a PCB with no BGA parts won't help you - let alone all that hotmelt glue, it will just stuff the board completely, so don't do that.

// Per.

Straighten that crystal on the right, it looks like one of the pins are almost shorting to it's housing.

That "crystal" has been straigntened, no shorts although it was touching a thermistor and the plastic looks slightly melted, could the heat have killed that? (Also, I assume you mean the pink/red, cylindrical, plastic wrapped component with 2-leads)

What happens when you connect USB, does the unit power on, and can the computer see the USB device in "Device manager" ?

No, and no

When connected to USB, can you measure any voltage at the battery terminals (no battery connected)

4.84 volts and the processor gets warm

I guess this has a mechanical ON/OFF switch on the edge of the PCB, check that for continuity when switched.

It connects

A reflow on a PCB with no BGA parts won't help you - let alone all that hotmelt glue, it will just stuff the board completely, so don't do that.

Forgot about the hot glue, and I guess your right about the bga...