How To Change  iPhone 4S Wi-Fi IC



for this work i used hot air gun, soldering iron, soldering paste, stencil for make legs on the IC and PCB rework station for preheating the board
HOT AIR TEMPERATURE MAX- 385ºC
HOT AIR AIRFLOW – 1 (ABSOLUTE LOW)
SOLDERING IRON TEMPERATURE – 400ºC
BOARD PREHEATING MACHINE TEMP – 85ºC

(on the video first 11 minute is real time before i remove IC from the board. the board needs time to getting enough hot, it must be very hot before you try to remove IC)

Nguồn: https://openworldleague.org/

Xem thêm bài viết khác: https://openworldleague.org/category/cong-nghe

25 Comments

  1. Hi can you tell me what kind of type are you using it's a copper tip or normal tip like hakko 900-m

  2. Use Kim wipes then assemble the unit
    Always use esd finger cots to prevent damage from static charging and cancer.
    Use esd clothes with full face mask with 3M ABE1 filter for organic an anorganic acidic vapors.
    Don't eat drink and smoke during these processes.
    The area of rework is a separated room esd flor bench mat and has extractor air filter that absorbe the fumes.
    When you handling chemicals and lead always pay attention as all these materials are toxic.

  3. 217 is the ultra wetting where the alloy is liquified.
    Use heat from bottom don't overheat the pcb this usually quick process you will see it when the chip settled down.
    Then cool the chip down clean the board with cleaning agent.
    Dry it
    Use kim

  4. When you remove the old chip use low melting point alloy that melts on 135C
    Tin the padded back and clean it with 2mm solder braid 3Swick branded.
    After clean it with cleaning agent KD-001

    Not sure if you get new chip but most of the time the old wont work (overheating issue)
    When you fit a new chip apply tiny amount of qualitek pf-600 tackling flux that has excellent wetting ability.
    Then set the heat to 220 as you use leaded alloy and this has melting point at 189C
    And the wetting is 217

  5. Someone mentioned about 385C

    Guys that's wrong !!!!!!
    The melting point of lead free alloy is 217C
    The wetting point is between 220C -230C

    The black stuff under the chip is the pcb paint.
    This usually ripen off because the chip is sealed with epoxy resin.
    To remove chip use heat from below and peel it from side to avoid damaging other components near by.

    Use tackling flux from qualitek or from fraser

  6. did you have power cut why you got the lights off or maybe sell the iphone pay electric bill

  7. Please answer my question asap: 
    @ 25:30 you apply, something what is that? For Reballing other devices i use soldering balls.
    Also, @ 32:00 you have another chip. Did you just decide to replace it?

  8. Hi there, I wanted to go through the steps. Tell me if I am correct. Any extra tips will be much appreciated!

    0:0011:00 – You're using the hot air rework wand set at 385ºC to remove the chip. You are protecting the board with polyimide film, correct?

    12:1021:40 – You apply flux and use the solder iron at 400ºC to soften and remove black glue, then use the solder wick to pick up the previous bits of solder.

    20:5524:15 – You're just removing more black glue, desoldering and picking off excess bits?

    24:4027:15 – You're sticking the IC chip to the stencil, applying soldering paste and heating it to 385ºC, correct? What do you use to stick the chip to the stencil? More polyimide film? Is the chip/stencil keyed? Meaning, it has to be in a certain direction to fit? 

    29:2534:10 – You're applying flux and heat at 385ºC to seat the new chip to the board. You heat through for a little over two minutes. I'm guessing you didn't need to apply any solder because the stencil provided that when you put the "legs" on. Is that correct?

  9. what kind of stuff you use to do this, special tape, pasta ,  needle and gun blower are you using sir ?

  10. I paid 2000 pesos btw so that's like 40 bucks I think wifi chip is cheap but the skills to do it is hard I guess I pay for the service more than the chip cost

  11. Really had a bad day fixing this now I have my wifi back I went to 3 technicians here in Philippines and they change like 4 wifi chips on the board but now it's working and they say the best way is to change the chip so I'm good to go the problem was on the way home my sim don't even get recognize and I use a alcohol and a quip and that's solve that but it gave like 4 hours of headache shit

  12. hi there, nice work and clean! i want to know what temperature have you used to remove the ic and what was when you solder the ic. also, what you use to reball the ic? it is something special?

  13. Hi! Love your work! I have a problem, the new wifi chip won't stick! I an realy new to this so i'm greatful for some help, i my hotair to 385c and solidiron 400c.

Leave a Reply

Your email address will not be published. Required fields are marked *