# Reverse Engineering The Dock Charger



## ZebCrs (Oct 24, 2011)

I got my desktop charger today and unpacked it only to rip it aparts to check whats inside.
By first view theese are the highlights:

The dock connector is 40 pins
Dock connector is on a separate small pcb with a 40 pin board to board connector to a larger board.
On this small pcb is a 12 pin MLF package marked:
AAU
NAD

Probably has a ground pad underneath.

The main pcb has a few more circuits and connectors on it.
There is a micro usb, a full size master usb, audio out and microphone jacks. A bit more exiting there is room for a HDMI connector as well there with unpopulated spaces for line filters and a hdmi circuit. By first look it seems to be a displayport or MHL to HDMI bridge chip of some kind. I is TQFP-48 package.
edit:
It seems to be a PI3VDP411LS from pericom
http://www.pericom.c...PI3VDP411LS.pdf

It is a displayport levelshifter / bridge to HDMI. It is the only 48 pin package I have found to match the input with the differential pairs.

The power supply is 20 VDC 65 Watts. It does not seem like the center connector is connected. The connector is the standard "IBM" charger, outer case ground, inner case + 20 vdc, center pin power diag.

There is a fet transistor between the dock connector and the psu marked FA1K18 and it is controlled by some regulator marked 920A4 in a SOT-223 package. The 20 VDC goes in on pin 2 and the tab on it.

the HDMI chip has differential pair inputs on pin 47,48 - 44,45 - 41,41 - 38,39

I will do my best reversing the whole schematic for this unit and split it into parts so we can make other chargers and hopefully add HDMI to the dock.

*Pinout Docking Connector Thinkpad Tablet*

1 charge 2 gnd
3 charge 4 hdmi pin 44 In D3-
5 Charger control (to pq2) 6 hdmi pin 45 In D3+
7 hdmi VDD 3.3V 8 gnd
9 gnd 10 hdmi pin 47 In D4-
11 USB Micro D- 12 hdmi pin 48 In D4 +
13 USB micro D+ 14 gnd
15 USB Master D- 16 nc
17 USB MAster D+ 18 nc
19 gnd 20 hdmi pin 29 SDA
21 gnd 22 hdmi pin 28 SCL
23 hdmi pin 41 IN D2- 24 hdmi pin 7 HPD_Source
25 hdmi pin 42 In D2+ 26 gnd
27 gnd 28 audio out L
29 hdmi pin 38 IN D1- 30 audio out R
31 hdmi pin 39 IN D1+ 32 headset inserted switch
33 gnd 34 mic inserted switch feed
35 USB micro + 36 mic inserted switch
37 gnd 38 mic tip
39 + 5V to usb master 40 mic ring

Pinout AAU chipAAU chip is audio amp.
audio out
pin 10 ring
pin 11 tip
pin 2, 7 gnd

Charger stuff :
The supplied DC apater is 20Volt 3.25Amps
In the dock there is a voltage regulator PV1. It is a 3.3 V LDO Tab has 20 volts in and pin 3 gives 3.30 Volts out.
There is also a FET in SSO8 (?) package. It is controlled by 2 transistors and works only as a switch.
On the base of PQ2 (pin 1, I guess it is the base) there is a float of 3.30 volts when there is nothing in the dock. The FET is OPEN and no voltage to the charger pins.
When grounding PQ2 pin1 (dock pin 5) the FET CLOSES and the charger outputs 20,5volts which basically is the same as dc power into the dock.

Now I am just waiting for the TPT to get fully charged so I can measure if there is any difference when fully charged.

Note:
By charging at 20 volts instead of 5 volts I understand why the charger only uses 2 pins into the TPT.
At 20 volts you can transfer 4 times the energy instead of just charging at 5 volts from USB powers. There is no need for step ups to charge the LI-Po battery as it would need more than 5 volts.

This is the schematics of the charger part:

www.r-888.com/tpt/schema.pdf

I am not sure of the 2 transitors if they are pnp or npn yet but the rest is how it is.
The original mosfet is a P-channel AON7403.
The regulator is just any 3,3 volt LDO.

The TPT charger control pin 5 gets a 3,3 volt float via the resistor to the left in the schematic. When it is connected the TPT grounds the pin and the FET lets current through.


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## dsw1ft (Oct 19, 2011)

ZebCrs said:


> I got my desktop charger today and unpacked it only to rip it aparts to check whats inside.
> By first view theese are the highlights:
> 
> The dock connector is 40 pins
> ...


Hacking hardware? This community is awesome!


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## rajamahal (Nov 1, 2011)

I think I found the parts for the female and male docking port connectors. The features on the pictures look pretty near identical to the docking port on the TPT. Hopefully this helps in your efforts to figure out how we can make a homemade charger. We would just need to reduce the voltage/amps from the psu to what the dock outputs, unless the chip also sends a sort of data signal to tell that its providing juice.

female: http://www.mouser.com/ProductDetail/JAE-Electronics/DD2R040HP2R1000/?qs=sGAEpiMZZMvd2mIcYG7oaBPmHh3ZnC2j%252bc%252bxfTSM%2fuw%3d
male cable: http://www.mouser.com/ProductDetail/JAE-Electronics/DD2P040MA1/?qs=sGAEpiMZZMvd2mIcYG7oaGMGyOaUl6J1nIDf0saGL3I%3d
male connector: http://www.mouser.com/ProductDetail/JAE-Electronics/DD2B040HA2R500/?qs=sGAEpiMZZMvd2mIcYG7oaGC50BWp6JGtnzFW1qxXQKU%3d

I could be wrong, but hopefully this helps


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## ZebCrs (Oct 24, 2011)

Cool, I just ordered a couple of sets of connectors of the variants they had. They should arrive on Friday.
Hopefully I will have time tomorrow to map out most of the connector. I will do some hires scans of the boards.
I have uploaded some pics here :http://www.r-888.com/tpt/pics


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## opnsrcaddict (Oct 17, 2011)

I'd love to be able to make a custom cable to provide audio out and charging for use in my car mount... It looks kind of messy with separate wires coming out of the side. Looking forward to seeing if you can come up with a pinout!


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## rajamahal (Nov 1, 2011)

ZebCrs said:


> Cool, I just ordered a couple of sets of connectors of the variants they had. They should arrive on Friday.
> Hopefully I will have time tomorrow to map out most of the connector. I will do some hires scans of the boards.
> I have uploaded some pics here :http://www.r-888.com/tpt/pics


It's times like these I wish I'd studied electrical engineering instead of mechanical, but if there's anything I can do to help moving forward (another part hunt like before) please let me know. There are many cool possibilities if we can figure out how to recreate the same circuit.


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## rajamahal (Nov 1, 2011)

ZebCrs...really appreciate your willingness to take your own dock apart. Would you agree that the easiest thing to tackle first would be figuring out the power circuit? Perhaps just a charger cable that ties right into the positive and ground of the 65 watt psu and goes right into a circuit that can feed one of those male dock connectors.

Since you have the dock and I would assume also a voltmeter, you can probably figure out what the circuit needs to entail pretty easily. I've got a laser printer and I've heard of people etching via a laser printout. If we can come up with a design and what components need to go on it, I feel like we could make a prototype charger for <$35 including non-lenovo 65 watt ac adapter.


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## rajamahal (Nov 1, 2011)

Here's what I found on the *voltage regulator* based on the info you shared....seems difficult or impossible to get in small quantity. Still not sure about the transistor, heck I don't even know the purpose of these things







It's a start, but time for bed!


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## rajamahal (Nov 1, 2011)

We would have to use something like these I believe, please confirm that the output to the tablet is 4.85 volts @ 400mA...

hole mount http://search.digikey.com/us/en/products/MIC2920A-4.8WT/576-2220-ND/1029102
surface mount http://search.digikey.com/us/en/products/MIC29201-4.8WU/576-2215-ND/1029074


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## ZebCrs (Oct 24, 2011)

Added pinout in post 1


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## andytiedye (Nov 2, 2011)

The Ideapad K1 appears to have a 40-pin docking connector too. Has anyone tried making a USB bus master cable for it?


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## rajamahal (Nov 1, 2011)

My goal is to hopefully help create a charging cable with the 65 watt 20volt psu that will work with the 40 pin docking port. Not sure how the LDO voltage regulator and fet transistor circuit would be put together though. We found the connectors and I think I found an appropriate LDO Volt. Reg. but have not identified a proper FET transistor. We know which pins need the positive and ground from the charger as well.

Need some assistance with the circuit design (though I don't think it's that complicated) and the FET transistor and we should be able to create a charger as good as the dock.


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## ZebCrs (Oct 24, 2011)

I am trying to figure out how the charger is started up now. Without the pad connected to the dock the regulator and connected fet does not start up. There is 1 control signal from the pad to some circiutry around the regulator.
I have to get my scanner working and do some scans of the boards. I have mapped out most of it now and will add some comments on the scans. Maybe I get my connectors in today or tomorrow


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## ZebCrs (Oct 24, 2011)

Regarding the voltage regulators. We just have to find a regular that works like the original setup. Find one with all integrated instead of external fet to control power flow. It is a bit more easy and a bit more expensive. The connector for the charger is really expenise anyways. It is about 10 € and the shipping is about 35€ !
But as soon as I can confirm the connectors are the correct ones we can start finding a cheaper supplier on them.
I can do a small schematic and a pcb that accepts most laptop chargers and 12 V dc car input to make it it more all-round usable.


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## ZebCrs (Oct 24, 2011)

I got the connectors in my workshop here now and can confirm it is the correct ones.

* DD2P040MA1 from JAE engineering is the correct cable connector. The Mouser part no is : 656-DD2P040MA1*

It is 9.08€ a pcs. and down at 4.82€ in 1000x. They have 111 pcs. in stock atm.


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## rajamahal (Nov 1, 2011)

MY DD2P040MA1 will probly come in tomorrow. Assumed it was the correct part. I'm going to try and get an old Lenovo psu from the tech guys at my workplace to avoid paying for that too.

I guess I'm not surprised that there is a control signal to the charger. I wouldn't know if we need to replicate this or if it could just be always on. Perhaps it's an easy addition to the final pcb anyway, sounds like you are working to try and find out. If there's anything I can help with, let me know!

Also I think it would be good to be able to use the standard Lenovo 90 watt 20 volt laptop charger, since they are cheaper on the second hand market than the new 65 watt one.


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## obscure.detour (Nov 2, 2011)

ZebCrs said:


> I got the connectors in my workshop here now and can confirm it is the correct ones.
> 
> * DD2P040MA1 from JAE engineering is the correct cable connector. The Mouser part no is : 656-DD2P040MA1*
> 
> It is 9.08€ a pcs. and down at 4.82€ in 1000x. They have 111 pcs. in stock atm.


So, correct me if I am wrong, but could we use the DD2P040MA1 connector to make a cable for the dock port. Would the other end of the cable be simply a USB male connector that we could connect to the current USB charger we received with our TPT's? Or is that adapter not fit to output what the DD2P040MA1 connector needs?


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## rajamahal (Nov 1, 2011)

obscure.detour said:


> So, correct me if I am wrong, but could we use the DD2P040MA1 connector to make a cable for the dock port. Would the other end of the cable be simply a USB male connector that we could connect to the current USB charger we received with our TPT's? Or is that adapter not fit to output what the DD2P040MA1 connector needs?


No this is basically replicating how the dock charger charges without having to buy the dock. This charger would be using a 65 watt or 90 watt, 20 volt AC Lenovo Power Adapter (brick) just like the dock does along with a 40 pin cable connector (see posts above) and some associated circuitry (Voltage Regulator) to bring the 20V down to 5V. It's not as simple as you are thinking. It will take some soldering, pcb board fabrication, etc.


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## ZebCrs (Oct 24, 2011)

You would need a power supply that can deliver more voltage and more current than the original. The USB standard does not allow that much power.
You would need a power that can give at least 2,5 Amps. 
The DD2P040MA1 connector is just a connector. You would still need a voltage regulator and some signaling from the tpt to the charger circuit.
Still working on that part. Between this I actually have to work too !


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## rajamahal (Nov 1, 2011)

ZebCrs said:


> You would need a power supply that can deliver more voltage and more current than the original. The USB standard does not allow that much power.
> You would need a power that can give at least 2,5 Amps.
> The DD2P040MA1 connector is just a connector. You would still need a voltage regulator and some signaling from the tpt to the charger circuit.
> Still working on that part. Between this I actually have to work too !


Don't we all....it's such a bother


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## andytiedye (Nov 2, 2011)

Does the Ideapad charger work on the TPT?


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## obscure.detour (Nov 2, 2011)

rajamahal said:


> Don't we all....it's such a bother


I didn't think the USB would be enough to power it. Yes, work is a bother, speaking of which I must tend do soon.








I am considering getting a dock and was just curious, I wouldn't want to imply that you don't have anything else to do than to rip apart Lenovo's products so we can simply make them better









I do appreciate both of your efforts though, as any and all information we can gather will help in our fight to make this tablet the _best_ experience.

Cheers.


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## ZebCrs (Oct 24, 2011)

I work with servicing audo and ligh equipment, and doing small proto types now and then.Have been doing electro and mechanical prototypes for about 14 years now. I love doing small reverse engineering stuff like this !


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## rajamahal (Nov 1, 2011)

I just got out of school for mech. engineering and participated in a thing called Baja SAE, where we built a one-person OHV from scratch, so I enjoy this stuff as well. Just wish I knew more about PMICs. Knew I should have paid attention in 'circuits for engineers' class.







Ghettofacturing a pcb board and housing will be the fun part for me....I'll just let you, ZebCrs, do the hard part! My connectors arrive today, so excited!


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## ZebCrs (Oct 24, 2011)

I've been working a couple of days now with a game for a tv show. "Volt Quiz" a game for 4 contestants, You answer right the others gets electrocuted and wrong..... 
Hopefull I can measure the voltage regulator from the charger tonight. There are 2 interesting signals there. The actual charging voltage and the control signal for the charger.


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## ZebCrs (Oct 24, 2011)

More updates in post 1 on the charging !
Seems it pushes 20 volts straight into the TPT !
Just waiting for it to charge up to max. now so I can find out if the charger enable signal changes when fully charged.


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## ZebCrs (Oct 24, 2011)

http://www.r-888.com/tpt/schema.pdf

This is a preliminary schematic for the charger. I am not sure of the 2 transistors if they are npn or pnp ones yet. The mos fet used is AON 7403 which is a P-channel transistor.
When the TPT grounds the charger control line the fet lets current through.
The voltage in to the charger is 20,5 Volts.
The regulator is just a standard 3,3 volt LDO.


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## ZebCrs (Oct 24, 2011)

Getting parts to build my test charger tomorrow !
I'll be using a 3.3 volt ldo than handle over 20 vdc input. One digital transistor as inverter for c ontrol signal and a highside switch to control powerline.


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## rajamahal (Nov 1, 2011)

zebcrs, when you get a chance could you post links to the part #s you purchased for the build? Thanks!


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## ZebCrs (Oct 24, 2011)

Now I have built the charger and it works just fine 
This is the schematic for my charger:
http://www.r-888.com/tpt/charger.pdf

I bought all parts from www.elfa.se.
2 x 100 kohm resistor
1 x U3 = LM3480IM3-3.3 Elfa part no : 71-014-51
1 x U2 = ITS410E2 Elfa part no: 73-266-86
1 x U1 = NC7S04M5 Elfa part no: 73-507-48

You would also need the JAE connector from Mouser.
And of course You need a laptop power that gives 20 Volts DC and at least 2 amps.The one that comes with the dock is 3.25 Amps at 20 VDC.


























The LDO needs to be able to handle over 20Volts on the input. This one has 30.
The inverter part can be any inverter that works on 3.3 volts. even a digital transistor but then You would need 100k pullup on the output.
The Highside switch is just a switch.... It just needs to handle 50-60 watts. I chose this because it was in stock and could handle the power without any need of extra cooling.

Just be sure which way You solder the connector as 20 volts on the wrong pins WILL KILL the TPT !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Double and triple check. The datasheet for the connector has a good drawing of this.
http://www.jae-connector.com/en/general_en.cfm?l_code=EN&series_code=DD2%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20%20&contact_number=&s_height=&l_con=&r_con=


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## rajamahal (Nov 1, 2011)

You're the man btw, but 2 questions. First, the 90W adapter should work just fine with all these components I'm assuming? (switch goes up to 5 A, etc.) Second, in what fashion did you connect to the pins on the dock connector. Just soldered wire? Thanks again for the help on this!


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## ZebCrs (Oct 24, 2011)

Yes, the 90 W adapter should work just fine. I am using a 70 W Dell adapter as a had a bunch of them lying around.
I just soldered wires to the pins. I'll see if it is possible to open the connector after it is closed.I was just planning to fill the connector housing with glue to make it mechanical stable.


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## obscure.detour (Nov 2, 2011)

Question for you guys. I believe this AC adapter is for the K1 IdeaPad. Here is the direct link. It is the Lenovo 18W AC Adapter-UL (Part# 78Y7365), and is listed on Lenovo's site under Tablet Accessories.

It looks like this plugs into the 40-pin connector in which you guys had via the dock. I guess my question is, would this work for the ThinkPad tablet? I cannot think of a reason why it wouldn't, unless the IdeaPad and the TPT have different power requirements which seems silly. I was looking to order one, but wanted to make sure. I am also dreading the scenario if and when I ask Lenovo support the same question, heh.


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## rajamahal (Nov 1, 2011)

One other question...I don't see a second 100K resistor between the charge and U2 in your actual build as shown on your schematic. Is that resistor interal to the switch? Also what wattage were your resistors?


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## ZebCrs (Oct 24, 2011)

I added a resistor from charger output to ground because there is no load when the charger is not connected. I just wanted to keep the float to 0 volts when not connected. If not it will float at around 9 volts.
The second resistor is not needed when using a real inverter circuit for charge control signal.


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## sonex293 (Nov 3, 2011)

Lenovo 18W AC Adapter-UL (Part# 78Y7365)



obscure.detour said:


> Question for you guys. I believe this AC adapter is for the K1 IdeaPad. Here is the direct link. It is the Lenovo 18W AC Adapter-UL (Part# 78Y7365), and is listed on Lenovo's site under Tablet Accessories. It looks like this plugs into the 40-pin connector in which you guys had via the dock. I guess my question is, would this work for the ThinkPad tablet? I cannot think of a reason why it wouldn't, unless the IdeaPad and the TPT have different power requirements which seems silly. I was looking to order one, but wanted to make sure. I am also dreading the scenario if and when I ask Lenovo support the same question, heh.


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## rajamahal (Nov 1, 2011)

Since its only 18 watts that part will not charge the tpt any better than the regular charger. The dock uses a higher wattage ac adapter.


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## konker (Nov 10, 2011)

sonex293 said:


> Lenovo 18W AC Adapter-UL (Part# 78Y7365)


Went down to a local Lenovo dealer to take a look at the A1 which I think is similar to the K1 & noticed that the connector for this charger is quite different from the TPT connector. There are additional contacts at the two ends of the connector which I did not notice in the TPT.


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## konker (Nov 10, 2011)

Lenovo is currently selling the Thinkpad Tablet Dock (Pat No.: 0A33953) with the 65W charger for US$41.99 here.


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## Sporty (Dec 17, 2011)

Is it possible that someone can build a extension cable for the tablet dock to charge the TPT?

I use a Moko Case for the TPT and I'm not happy to put the Tablet evey evening out and at morning back to case. BTW, I'm from Germany.


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## SoonerLater (Aug 31, 2011)

Bump...

http://forums.lenovo.com/t5/ThinkPad-slate-tablets/High-voltage-charging-WITHOUT-dock/td-p/669989


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## ZebCrs (Oct 24, 2011)

I have done some research and calculations here now and found out I can do a production of 25 units if I get orders.
A quick econimcs on the production costs:
25 psu's 3800 NOK
parts,conn 1700 NOK
pcb 1400 NOK

Total of 6900 NOK pc. 276 nok
1190 USD pc. 47,6 usd
905 EURO pc. 36,2 euro

This is whaty it cost to produce these. If I only make 10 the part cost will be about 10% higher and the pcb cost will stay the same.

If anyone can come up with better prices we ca make them even cheaper.
The first thing to cut cost on is the pcb. If anyone can produce these double sided pcb's at about 2,5cm x 3cm that will give a significant cost reduction.

Here is the part list.
Power supply 19 or 20 volts at 60-90 watt. Whatever we can get cheap. Laptop surplus ?????

Customer Part No. 
Order Qty. 
Price
(NOK) 
Ext.
(NOK) 
*Mouser No:* 512-NC7S04M5  *Mfr. #:* NC7S04M5 *Manufacturer:* *Fairchild Semiconductor* *Desc.:* Inverters Inverter *RoHS* *RoHS Compliant*

Packaging Choice:
Cut Tape 
*Availability*
25 Dispatches Now kr 2,64 kr 66,00 
*Mouser No:* 926-LM3480IM33.3NOPB  *Mfr. #:* LM3480IM3-3.3/NOPB *Manufacturer:* *National Semiconductor (TI)* *Desc.:* Low Dropout (LDO) Regulators 100MA,QUASI LDO LINEAR VLTG REG *RoHS* *RoHS Compliant* *Info:* View Additional Product Info

*Availability*
25 Dispatches Now kr 5,60 kr 140,00  
*Mouser No:* 656-DD2P040MA1  *Mfr. #:* DD2P040MA1 *Manufacturer:* *JAE Electronics* *Desc.:* I/O Connectors 40P CABLE PLUG *RoHS* *RoHS Compliant*

*Availability*
25 Dispatches Now kr 48,05 kr 1 201,25 
*Mouser No:* 726-ITS410E2E3043  *Mfr. #:* ITS410E2 E3043 *Manufacturer:* *Infineon* *Desc.:* Power Switch ICs - Power Distribution Smart High-Side PWR SWITCH 65V 12A *RoHS* *RoHS Compliant*

*Availability*
25 Dispatches Now kr 11,23 kr 280,75

[/indent]

Or if any one want's to build these I will be happy to supply pcb production files for free. I have not made them yet but it would take me an hour to put them toghether as I only built mine on an experimental board.


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## obscure.detour (Nov 2, 2011)

@ ZebCrs,

This is amazing news! I'd definitely be willing to pitch in for a charger like this. Did you see my post on the Lenovo board about suggesting monoprice.com make these for our community?


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## Sporty (Dec 17, 2011)

@ ZebCrs,

I'm interested in one. Is it possible to build one? Maybe you can sell these Chargers on ebay, if there are not enough members interested in this chargers here.

for more info let us talk through PM


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## paperclip69 (Feb 6, 2012)

HI

Very interested in this, i would pay to get one but i am also willing to get one made if purchase isn't an option in the short term.

any chance you could upload a picture of your charger? also any plans etc on the pcb would be great, i know someone who could maybe make this up for me if they have enough plans etc.

i have done some electronis but i will hold my hands up and say this is a lttle passed what i am able to do.

really keen to get something so i can fast charge this thing while being able to write on it on my desk.

cheers

Tom


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## ewhiteway (Mar 11, 2012)

I'd be in on buying a few of these.. Also if you could me the connector to the 20V charger a pass through so I can still chage the laptop on the 1 power supply.


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## dartz (May 11, 2012)

Would buy one. PM me if still possible! Thanks.


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## reox (Jul 16, 2012)

@ZebCrs: Can you upload the schematics again, maybe as picture? most of the names of the parts are not shown or are just a ?...
thanks!


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## cybernob (Aug 13, 2012)

@ZebCrs great work by the way thankx. Can you upload the charger cad file if possible?
thanks!!


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## c0psrul3 (May 18, 2013)

This is beautiful, I'm interested in helping build these, buy one, work on the design / minimize footprint, use for alternate chargers, add USB host, usb micro pass thru
anything to get this dock out of my backpack!

<<has experience


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## scstraus (Jun 14, 2013)

I'd buy one of these too. It seems to be the same dock as for the thinkpad tablet 2. Even better, I'd take just an adapter from the 65 watt PSU to the dock connector. That way I could reuse my kensington absolutepower from my laptop for quick charging my tablet.


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## Agris (Jul 5, 2013)

Dear ZebCrs,

Thank you for revealing TPT charge secrets. Previously this day I tried to repeat your acheivments, but failed.
Your pinout doesn't match mine inside my ThinkPad Tablet.
Pins 1 and 2 (see on picture no.1) are soldered together on my motherboard.
GND pins are not the same as your pinout has.

I've double checked drawings of connector from jae-connector - nothing common.
Does your TPT has same issue or I just have different version of hardware platform?

Second question here. Your small PCB board with transistor you developed - it that really required? If TPT is powered with 20vdc directly, why you need to add additional schematics? This moment is not clear from previous discussion.
I suppose, 3.3V is required (as you wrote) on PIN3 to enable TABLET to accept 20V on PIN1? Or not - PIN1 has no key and accepts 20 volts anytime?

Thanks in advance,
Alexander.


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## Agris (Jul 5, 2013)

Ok, I spent some time discovering.
Finally - my TPT is charging smoothly with 20VDC soldered directly to motherboard without any transistors or whatever.
What I did: +20VDC is soldered to pin 1 (and pint 2 - they're soldered together on my motherboard), GND soldered to any ground, like shield of dock connector, or USB ground, or whatsoever.
Pin number 1 on motherboard is marked with tiny white arrow (see picture above in post no.52)
That's it. Now TPT charges in two hours instead of 8. Great!

Thanks ZebCrs!!!


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## aan (Aug 24, 2013)

Agris said:


> Ok, I spent some time discovering.
> Finally - my TPT is charging smoothly with 20VDC soldered directly to motherboard without any transistors or whatever.
> What I did: +20VDC is soldered to pin 1 (and pint 2 - they're soldered together on my motherboard), GND soldered to any ground, like shield of dock connector, or USB ground, or whatsoever.
> Pin number 1 on motherboard is marked with tiny white arrow (see picture above in post no.52)
> ...


hi... i am new to this site.

@agris can u please upload some pictures of these connections.

thanks


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## jbaiter (Sep 7, 2013)

So this means that all we have to do for a charger would be to obtain that plug from mouser, a 20VDC power supply, wire up the power supply to the plug with the voltage on pin 1 and we're good? That sounds almost too good to be true!


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## tobi1986 (Jan 18, 2014)

Hey guys,

brand new here and what i really need is a way to charge my thinkpad tablet again without using the mini usb port.

How can i order on of your docking stations? they do charge without the mini usb port as far as i understand 

Thanks for your help! i have searched the web for days to find an option how to get my baby up and running.

tobi


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## sakunamary (May 11, 2014)

schematic link is broken now, can anyone fix it or rebuild it .thanks a lot!


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## explit (May 20, 2014)

ZebCrs said:


> I got my desktop charger today and unpacked it only to rip it aparts to check whats inside.
> By first view theese are the highlights:
> 
> The dock connector is 40 pins
> ...


Hello. Can you upload the pics and shematics one more time? The link is broken now...


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## MacGyver_Wildfire (Oct 26, 2011)

Hey,

can you upload the schematic from your charger ? Did you tried your the HDMI conection ?

I have the original dock and want to add HDMI. Do you think it is enough to add the PI3VDP411LS2 and a HDMI port ?

Thanks,


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## TonyW1967 (Aug 23, 2014)

Well, I've just bought a Thinkpad Tablet 1 and having just found a dock for it, I was most displeased to find that the HDMI Function doesn't work when the tablet is docked!

I cut a slot for a male mini HDMI Connector in the plastic next to the Dock Connector, threaded the male connector through the slot and into the female HDMI Port and the HDMI Function works right up until the tablet connects with the dock connector.

Soooo, my question is (and please bear in mind I am no electronics whizzkid), is there any way I can adapt the dock electrics to enable the HDMI Function to work while the tablet is docked?


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## dvsmiller (Apr 23, 2015)

Based on Agris' post and some investigation of connector manufacturer JAE's datasheets, I believe Zebcrs pinout is wrong. Here is what I believe it should be:

1 Charge 21 Gnd
2 Charge 22 HDMI Pin 44 IN D3-
3 Charger Control 23 HDMI Pin 45 IN D3+
4 HDMI Vdd 3.3V 24 Gnd
5 Gnd 25 HDMI Pin 47 IN D4-
6 USB Micro D- 26 HDMI Pin 48 IN D4+
7 USB Micro D+ 27 Gnd
8 USB Master D- 28 NC
9 USB Master D+ 29 NC
10 Gnd 30 SDA
11 Gnd 31 SCL
12 HDMI Pin 41 IN D2- 32 HDMI Pin 7 HPD_Source
13 HDMI Pin 42 IN D2+ 33 Gnd
14 Gnd 34 Audio Out Left
15 HDMI Pin 38 IN D1- 35 Audio Out Right
16 HDMI Pin 39 IN D1+ 36 Headset inserted switch
17 Gnd 37 MIC Inserted switch feed
18 USB Micro V+ 38 MIC inserted switch
19 Gnd 39 MIC tip
20 USB Master 5V+ 40 MIC ring

I have verified 3.3V on pin 4 and several of the grounds. I connected +20V to pin 1 and grounded pin 5 per attached photos. Works great. The tablet needs 20V on Pin 1 for charging to work. I tried 5V just in case I got the pinout wrong and I did not get the charging icon. I haven't verified operation of the other signal pins (for USB, HDMI, etc.)

Tablet Dock Connector Tablet Dock Connector
'Top' side 'Bottom' side














Parts purchased from Digikey:
Description  Digikey PN
JAE 40 Pin dock connector 670-1024-ND
20V 50W AC/DC power supply 62-1177-ND
DC power jack 732-5931-ND

I used a cable from a defunct USB cable to wire the connectors together. The DC jack lets me plug my new adapter cable to the power supply. The power supply also needs a typical 3 prong computer AC cable. I had some lying around from old computers.


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## explit (May 20, 2014)

Hello all.

Did anybody has a working USB-Host soldered to this 40pin JAE Connector ?

It would be cool to have charging and an additional USB Host Port on the same time.

I soldered the USB Connector on this PINS:

20: USB MAster 5V+

19: GND

8 USB Master D-

9 USB Master D+

But it's not working.

I tryed to connect an USB Mouse to the USB-Host Port, but it got no 5V i think.... :-(


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## ramamoorthy (Mar 15, 2016)

dvsmiller said:


> Based on Agris' post and some investigation of connector manufacturer JAE's datasheets, I believe Zebcrs pinout is wrong. Here is what I believe it should be:
> 
> .........
> Tablet Dock Connector Tablet Dock Connector
> ...


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## reox (Jul 16, 2012)

Does someone has a mirror of the schematic anywhere?
Original site is offline and not mirrored by archive.org.
Thanks in advance!


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