Problems with iPhone 5V car power supply

Discussion in 'Power Electronics' started by sacher, Jan 16, 2018.

  1. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Hi, since I'm new to this forum I would like to first introduce myself.
    I'm from Rome, Italy (so please be patient with my english!) and I'm a total beginner in the electronics field.

    My first tread concerns the possibility to use my old phone as a localization device for a friend motorbike (anti-theft device).
    We would like to use an old iPhone GPS-Glonass module to track the bike position.
    The only problem is to keep the phone constantly connected to the bike 12V battery to ensure a proper battery life. We decided to buy a 12V to 5V converter and a standard USB charging cable (a cable with a USB Type "A" connector on one side and an Apple's proprietary Lightning connector on the other). The idea was to cut-out the USB connector from the cable and to connect the red and black (+5v and GND) wires to the adapter, leaving the white and green wires unconnected. In my mind the all thing looked like an easy task!
    Unfortunately, the "thing" is not working: the phone is not showing the expected signal of "charging status" when connected.
    Attached you can find a picture of the adapter and the cable.
    Can someone please help me to understand whats happening? I read that the Lightning connector uses a couple of integrated circuits inside the small plastic body. Probably this could be the reason for my problem. Is there a workaround for this?
    Thank you very much
    Simone
     

    Attached Files:

    sacher, Jan 16, 2018
    #1
    1. Advertisements

  2. sacher

    73's de Edd

    Joined:
    Aug 21, 2015
    Messages:
    2,310
    Likes Received:
    762
    Location:
    Texas
    1. Advertisements

  3. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Hi 73's de Edd! Yes, I think you are right! But, before being cut in two parts, the USB to lightning cable was properly working and, thus, the circuitry embedded in the lightning connector should be able to get the required handshaking even after the splitting. Maybe I need to connect someway also the green and white leads (?) but I really can't find out how. Even reading the chipworks page you posted above I wasn't able to find any correction to solve my problem.
    Thank you
    Simone
     
    sacher, Jan 16, 2018
    #3
  4. sacher

    BobK

    Joined:
    Jan 5, 2010
    Messages:
    7,212
    Likes Received:
    1,504
    Location:
    Worcester, MA
    You answered your question. You need to connect the green and white wires. Apple phones looks for specific voltage on these wires to set the charging current.

    Bob
     
    BobK, Jan 16, 2018
    #4
  5. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Hi BobK! Thank you for your reply!
    My question is:
    how do I have to connect them?
    I'm afraid I could cause problems with the phone doing the wrong connections!
    Simone
     
    sacher, Jan 16, 2018
    #5
  6. sacher

    BobK

    Joined:
    Jan 5, 2010
    Messages:
    7,212
    Likes Received:
    1,504
    Location:
    Worcester, MA
    Why not just use a USB cable , as is?

    If not, just connect them the same way.

    Bob
     
    BobK, Jan 16, 2018
    #6
  7. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    If you look at the picture you will see that I don't have a USB connector to use. I have two wires coming from the 12V to 5V adapter.
    Now the problem is that the USB is made of 4 wires: GND (black), D+ (white), D- (green), +5V (red)
    while
    On the adapter side, as shown in the picture, I have only 2 wires: GND (black) and +5V (red).
    What do I have to do with the D+ and D- (white and green) wires?
     
    sacher, Jan 16, 2018
    #7
  8. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Just in case someone else should face the same issue here we have a possible solution...
    Just finished reading this interesting post:
    https://www.quora.com/What-is-the-difference-between-a-USB-charging-cable-and-a-data-cable
    Seems pertinent to my questions. Apparently, I should try to short-circuit the green and white wires.
    As soon as I try and in case of any positive consequence, I will post to confirm.
    In the meantime, should someone else have anything to add... it will be very very welcome!
    Thank you all
    Simone
     
    sacher, Jan 17, 2018
    #8
  9. sacher

    73's de Edd

    Joined:
    Aug 21, 2015
    Messages:
    2,310
    Likes Received:
    762
    Location:
    Texas
    ahhhh . . . . Mon Simone . . . .

    You are talking USB . . . .on your info . . . . you no have USB.

    You are using a Lightning connector fitting (PROBABLY a certified 100 % FAUX . . . import)

    Your phone is wanting / HAVING to make an initial digital handshake connection between the "adapter" to be sure that there is not being a piece of crap being connected to its inputs far end .
    That has to be done thru the Digital+ and Digital- wires with a VERY special, single buss serial digital stream and your adapter has to have the SPECIFIC Sony interfacing chip to receive and communicate back to the I-phone 5.

    With you not having an OFFICIAL SONY approved power adapter, there will be NO communication for confirmation and no power control will be initiated.
    Upon detection of a Lightning connector plug in . . . .your phone sends the digital query . . ." What do you want . . . and even MORE important WHO are you "
    No connection or no intelligent and proper connection reply comes forth . . . . so after a dormant time out, the I-phone detects that there is still a plug in . . . . another query is sent . . . . . ad infinitum . . . until the Lightning connection is unplugged.

    There is even the need for Lightning connector to I-phone 5 INITIALLY having confirmation, SINCE its plug is unkeyed, you can plug a lightning connector in BOTH ways , up or down, and the circuitry routing path is then compensated for by digital handshaking.

    LOOKS like you are going to have to bite the bullet and use a REAL SONY / or /LICENSED Cigar lighter adapter with its chipped Lightning connector on the end to plug into the I-phone.
    The only mod then would be to get the cigar type plug with its dual spring negative connector and central pin positive connector then interfaced into the motorcycle battery.
    AND THEN you need to insert current monitoring into that battery 12VDC supply line to see both the standby current pulled by the I-phone in standby mode.
    PLUS I don't know what your " bike" is for its battery.
    I DO know that I had one gawd awful big 1200cc HARLEY that mainly was dependent upon its one "hog" of an alternator with it only incorporating a minimalistic battery.

    Your best solution will probably be one of the dedicated GPS trackers made specifically for this theft purposing. Irregardless of your already having a "free" I-phone.

    On evaluating your "AUKEY" brand unit Lightning connector, did it come with pigtail leads like that on the wire end ?
    If mine to evaluate, I would be taking an ohmmeter and using its LOWEST ohms setting or possibly initially, its diode test /tone BEEP continuity position and check from the BLACK wire to see if there is direct connection to one of the Lightning pins gold connections.
    Then the same testing for both the Digital + and - wires and the final real test is if the RED
    wire has direct continuity to one of the Lightning pins gold connections.
    On a verifiable Sony unit that would be the connection that would / could be solid state switched
    between connected or disconnected connectivity, either at that point or additionally within the cellphone battery controller circuitry as per a valid digital activation.
    If a direct connection is being between the RED and a Lightning pins gold connections, one would suspect this to be a unit without its digital encoding / decoding electronics .

    MO' INFO:

    http://www.dailymail.co.uk/sciencet...ble-stop-parties-making-cheaper-versions.html

    https://www.apple.com/shop/product/MD818AM/A/lightning-to-usb-cable-1-m


    73's de Edd
     
    Last edited by a moderator: Jan 24, 2018
    73's de Edd, Jan 17, 2018
    #9
  10. sacher

    BobK

    Joined:
    Jan 5, 2010
    Messages:
    7,212
    Likes Received:
    1,504
    Location:
    Worcester, MA
    I use my iphone with lightning connector with all kinds of adapters and USB ports on computers and have never had it refuse to charge. Yes, it might be charging at 500mA or so, but it does charge. My 10 year old desktop is certainly not talking the proprietary Apple protocol.

    Bob
     
    BobK, Jan 17, 2018
    #10
  11. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    73's de Edd, I'm from Italy, not France! :D

    The cable is froma Amazon (AUKEY) and was fitted with one USB Type A and one Lightning connector at the ends. Then I decided to cut the usb end to connect the wires directly to the voltage adapter.
    Yes, the cable it's not an apple genuine one but I can ensure that is 100% compatible and personally tested before the cut. Moreover, I tested it with plenty of genuine and non-genuine plug adapters (both 220V and 12V) and it was always handshaking properly...then, after "the cut" no handshaking. The conclusion is that the green and white wires must be connected to something when you plug the USB, even using the worst chinese usb adapter on the market! My question is just how and where are this two wires connected once the USB is plugged.

    Ok, sounds clear now.

    Yes! This is also our workaround at the moment, and it's working well! But I would really like to understand why the original idea is not working. Sorry, I know I could seem a little stubborn :) but I definitely don't want to give up!

    The bike is a Triumph Bonneville, and the battery should be a lead acid battery with 12V and 7Ah.
    Yes, we need to solve somehow the problem of the standby draining but firstly the lightning connector! :)

    We already tested one of those (we spent around 100$ so, it's not a matter of money) but, believe me, you will never find one with the easiness and the integration you have when you search the position of an iphone from another iphone! It's way more effective and fast! And moreover (and this is particularly important) usually they rely only on GPS signal (not using the other GNSS satellites constellations), they are slow to fix the satellites (compared to the phone) and they are unable to calculate the position using cellular or wifi signals. This is particularly important when you are looking for something that could be out of the satellites signal (inside a building ore elsewhere).

    No, there was an USB type A connector on that end of the cable.

    Ok, it's a good idea but I'm pretty sure that the lightning connector is provided with all the electronics since, as I said, before being cut was properly handshaking!

    Thank you!
     
    Last edited by a moderator: Jan 24, 2018
    sacher, Jan 18, 2018
    #11
  12. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Yes BobK, I agree but the point is that even inside a wall plug adapter the data wires should be somehow connected in order to have a proper handshake. With my old iphone 4S (with the old apple 30 pin connector) the black and red wires where sufficient to make things work (white and green wires unconnected) and no handshaking was required.
     
    Last edited by a moderator: Jan 24, 2018
    sacher, Jan 18, 2018
    #12
  13. sacher

    Alec_t

    Joined:
    Jul 7, 2015
    Messages:
    2,390
    Likes Received:
    618
    Location:
    Wales
    Have you checked the cut-off plug to see if the white and green wires in it have any measurable resistance to the black and red?
     
    Alec_t, Jan 18, 2018
    #13
  14. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Hi Alec_t.
    Not yet. As soon as I try I will post the results.
     
    sacher, Jan 18, 2018
    #14
  15. sacher

    BobK

    Joined:
    Jan 5, 2010
    Messages:
    7,212
    Likes Received:
    1,504
    Location:
    Worcester, MA
    BobK, Jan 18, 2018
    #15
  16. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Following up to your suggestion I tried to measure the resistance between the data wires and the black and red ones. The resistance is infinitive for every couple of wires combination.
    I also took the opportunity to find out the lightning pinout and found the following resistance values:
    - black wire connected to PIN1 and connector body with 0,3 ohm resistance
    - red wire connected to PIN5 with 0,4 ohm resistance
    - green wire connected to PIN2 with 0,5 ohm resistance
    - white wire connected to PIN3 with 0,5 ohm resistance
    The pin numbering is as shown in the attached picture.
     

    Attached Files:

    sacher, Jan 24, 2018
    #16
  17. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Yes BobK, I definitely agree with you. Thank you very much for your suggestion!
    The adapter I have is able to provide 3A of current thus my option would be third on the link you provided.
    White wire (D-) 2.0V
    Gree wire (D+) 2.75V
    After some computations on the voltage dividers, I found that I should need the following four resistances:
    - R(1)=15kOhm between red and white wires and R(2)=10kOhm between white and black wires
    - R(3)=8kOhm between the red and green wires and R(4)=10kOhm between green and black wires
    Could you please confirm that I'm doing right?
    Thank you again
    Simone
     
    sacher, Jan 24, 2018
    #17
  18. sacher

    Alec_t

    Joined:
    Jul 7, 2015
    Messages:
    2,390
    Likes Received:
    618
    Location:
    Wales
    Use 8k2 instead of 8k?
     
    Alec_t, Jan 25, 2018
    #18
  19. sacher

    BobK

    Joined:
    Jan 5, 2010
    Messages:
    7,212
    Likes Received:
    1,504
    Location:
    Worcester, MA
    Yeah, they calculate out close enough, but as Alec suggests, 8.2K is a standard resistor and it actually comes out closer.

    Bob
     
    BobK, Jan 25, 2018
    #19
  20. sacher

    sacher

    Joined:
    Jan 16, 2018
    Messages:
    11
    Likes Received:
    0
    Yes, from the computations I mentioned in my previous post comes out an 8.2kOhm resistor but, since I'm totally unfamiliar with electronics components, I decided to round off the value to 8K thinking that resistors with 8.2k cannot be found. Who would have thought it could be a standard value?! :rolleyes:
    I will look around for my four resistors and try to connect everything.
    Then I will let you know the results. I think it will take some time to find a shop that sells resistors in 2018...maybe will be easier to buy them online or ask some friends.
    In the meantime, I would really like to thank you all for the precious support.
    Simone
     
    sacher, Jan 26, 2018
    #20
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.