Override EMIF

[djanib]

A lot of people ask me, how to override EMIF ESD protector.
I have no time to answer to all of them. Because of my time I’m making this topic.

First of all,,, sorry for my bad English, and I hope it will be enough to understand.

For example, I choose Nokia E66. Close to display connector, we have 3 EMIF chip.
Two of them are for display control, and one for S60 Extra keyboard under display.

EMI Filter is designed to suppress EMI and RFI noise and to discharge
Electrostatic from air 15kv and from direct contact 8kv.

In next pictures I will show how I do if I don’t have original EMIF.

This is E66 MainBoard.

Main Flat connector - X2400
Left - Z2401
Midle - Z2400
Right - Z2402

[djanib]

Next, I have to remove this Right EMIF Z2402 (Hot Air), because I have E66 with no working S60 keyboard.

After removing, all contacts are unusable, and we have to clean it.
Next pictures showing how bad is after removing and how must be before you begin override or replace with new one.

[djanib]

In this case I have to replace or override EMIF07-LCD02F3.
Don't wait and don't ask any more for overriding schematic.

It is so simple procedure. Look at schematic for EMIF. Have 18 connections point and all of them are marked with (I) as Input, (O) as output and GND as ground. GND Signals you can forget simply, because all of them are shorted on Main Board.

What we have to do ?
Just short Ix with Ox. In this case:
I1-O1
I2-O2
I3-O3
I4-O4
I5-O5
I6-O6
I7-O7

[djanib]

Ok. This is clear. Now let’s go and make small bypass between points.
For this I’m using electronic USB microscope to make pictures for you, and normal microscope for work. Electronic make one nano sec late picture and this will confuse me during work. That’s why I use normal microscope to make bypass.

After I finish with all it looks like this:

[djanib]

Last step.
After remove EMIF and make bypasses we have open contacts. Hot, cold, wet hands and other similar situation, will expose contacts to oxide. Oxide between contacts make problems like, indicate pressed key, keyboard again not work, some work some not. To prevent this situation we need just small part of plastic glue (silicon) or something like this. This will protect our work.

Protected:

[djanib]

Finished. Nokia E66 work like a charm. In this attachment you have some HiResolution picture, non resized.

I hope this will help to all,,, what is and how to do override EMI filters.
It is so easy to find all schematics for EMI filters. Just use google to find PDF:

emif07-lcd02f3
emif10-1k010f1
emif10-com01f2
emif10-lcd02f3
etc............................

BR
DjaniB

[waqarN70]

good work but i prefer to replace ic with new 1 its not so costly

[djanib]

Yes I have it to, more then 50 pcs emif07-lcd02f3.

I did it just for example, and to save my time from milion question "how to...".