Thinkpads Forum

Since IBM once again changed their DC adapter for their T-series, I cannot use a brick power supply I purchased from Radio Shack. I am looking for a new plug so that I can make an adapter, but I cannot find one of the right size. The closest I can find is 7mm. See this link:

http://www.powerstream.com/dc-tips.htm

I think the T60 uses ~9mm tip. Any suggestions on where to hunt?

Good luck -- I've never seen anything remotely like it.

Is it really worthwhile to make your own rather than just get it from Lenovo? I'm sure that's part of their plan in using such an odd connector but at some point it's less costly to just raise the white flag and go buy one.

-darren

onix wrote:Since IBM once again changed their DC adapter for their T-series, I cannot use a brick power supply I purchased from Radio Shack. I am looking for a new plug so that I can make an adapter, but I cannot find one of the right size. The closest I can find is 7mm. See this link:

http://www.powerstream.com/dc-tips.htm

I think the T60 uses ~9mm tip. Any suggestions on where to hunt?

Why do you want to make an adapter?

I can see a few reasons, but they are pretty far out there.

Why not? I want to make use of a second power brick that I bought just a year ago. Plus it's great to have two adapters - one for work & one for home. It's a pain to carry the adapter back and forth & it's easy to forget.

christopher_wolf wrote:
Why do you want to make an adapter?

I can see a few reasons, but they are pretty far out there.

What is the rating on the old power brick? Is it adjustable?

The new power brick and the old power brick (T4x) are not the same inside. The new ones are higher voltage and power rating. Doesn't seem like a particularly safe thing to do...

IBM makes different tips to prevent power screwups. There are enough questions in here and sufficient lack of knowledge about basic Ohm's Law that many people in here asking about power bricks would connect the wrong power brick if they were not otherwise prevented, and then come back with the question "What happened?". Safety and proper operation demand using only the adapter suggested by IBM. ... JD Hurst

I feel pretty comfortable with doing this - my degree from MIT in EE should help. Anyways, yes there is a voltage adjust up to 20V. It doesn't allow up to 90W of power though - tops out at ~85W. If there is not enough current, then there is not enough - but I suspect little damage occuring & I will have to computer turned off to reduce the current

It's hard to imagine a screwup with not enough power. It's frustrating that the adapter has changed though.

jdhurst wrote:IBM makes different tips to prevent power screwups. There are enough questions in here and sufficient lack of knowledge about basic Ohm's Law that many people in here asking about power bricks would connect the wrong power brick if they were not otherwise prevented, and then come back with the question "What happened?". Safety and proper operation demand using only the adapter suggested by IBM. ... JD Hurst

The connector in the thinkpad is no longer soldered to the mobo - it's connected by cable. You could replace it with a port that matches your connectors. It would be a one of a kind! I'm sure nothing bad could happen!

-darren

onix wrote:I feel pretty comfortable with doing this - my degree from MIT in EE should help. Anyways, yes there is a voltage adjust up to 20V. It doesn't allow up to 90W of power though - tops out at ~85W. If there is not enough current, then there is not enough - but I suspect little damage occuring & I will have to computer turned off to reduce the current

It's hard to imagine a screwup with not enough power. It's frustrating that the adapter has changed though.

jdhurst wrote:IBM makes different tips to prevent power screwups. There are enough questions in here and sufficient lack of knowledge about basic Ohm's Law that many people in here asking about power bricks would connect the wrong power brick if they were not otherwise prevented, and then come back with the question "What happened?". Safety and proper operation demand using only the adapter suggested by IBM. ... JD Hurst

Well, go ahead then my EECS friend.

If nothing else, at least you will get it to charge the system when it is off; you wouldn't get very good results both charging and powering it at full blast as compared to the IBM adapter....Still, it would look good on a resume or a nice project to have.

In any event, let us know how this goes.

I just checked the Targus brick that I bought a few months ago and it includes a sack of 8 various size connectors. One of them is identical to the connector on my t60p and has 20 stamped on the side. The brick is rated for 65W max on ac and 70W max on dc. The output voltage shows 15-24 but is not manually adjustable. So I guess that it automatically adjusts somehow. The model number is 800-0084-001A. Don't know if you can buy an individual connector from Targus but might be worth a try.

There was another thread a while back about this.

Lenovo wanted to up the power output, so it made sense (in broader engineering terms) to up the voltage as well. There are any number of reasons why you would want to minimise current.

Though off topic, BMW is toying with higher voltage car batteries, i.e. 48VDC. It's to power their many sensors and electronics.

High voltage has two advantages that are immediately apparent to me. It allows lower voltages to be pulled off easily - batteries are usually multiple cells in series, with each cell contributing a few volts. Going from low to high is more complex, requiring a DC -> AC-> DC conversion. It can be pretty efficient, i.e. > 90%, but requires additional electronics.

The second advantage is that for the same power, there is less current draw and hence less power dissipation over the wires connecting to the loads.

beeblebrox wrote:May I ask here, why the voltage went up to 20V?

I don't understand. In my opinion the voltages should go down.
In 15 months, when LEDs will have taken over, the highest voltage on the system would be 5V.
20V input to a 5V system is way unefficient.

Right now, the 12V output from the battery is only for the HV Inverter, nothing else.

A very strange Lenovo decision. I see new power bricks coming in 15 months, again...

Yeah right...
but in the BMW you have currently at least 50 microprocessors, ACon., NavigationPC, window heater, etc. Xenon headlamps, Multimedia stuff, etc.
In worst case you might have a few dozens Ampère running through the wire, which is odd.

Do you know, that up 30-40% of a modern 6 cylinder engine is needed to just run the electronics?

I used to use a company BMW for some time. When you use it regularly in city traffic and have all gadgets turned on, it might (!!) happen, that your battery dies, because the recharge current is too low. You have drive fast for some time to recharge

But we are talking about a "Notebook!"
Why the hell do I need all multiprocessor stuff and super fancy big graphics chips, if I need long battery time?
For the past 3 years the power consumption has not changed a bit. The processors have become much faster, still they suck more power than ever.

beeblebrox wrote:Do you know, that up 30-40% of a modern 6 cylinder engine is needed to just run the electronics?

Show me an engine that produces < 20kW and I might believe you.

jhkaska wrote:I just checked the Targus brick that I bought a few months ago and it includes a sack of 8 various size connectors. One of them is identical to the connector on my t60p and has 20 stamped on the side. The brick is rated for 65W max on ac and 70W max on dc. The output voltage shows 15-24 but is not manually adjustable. So I guess that it automatically adjusts somehow. The model number is 800-0084-001A. Don't know if you can buy an individual connector from Targus but might be worth a try.

The #20 tip is listed for select Dell computers. The important thing to remember is that the tip actually adjusts the voltage of the adaptor, so the connecter may fit, but the voltage may be wrong.

I'd test the voltage first with the #20 tip, and see if it matches the Thinkpad adaptor.

jdhurst wrote:IBM makes different tips to prevent power screwups. There are enough questions in here and sufficient lack of knowledge about basic Ohm's Law that many people in here asking about power bricks would connect the wrong power brick if they were not otherwise prevented, and then come back with the question "What happened?". Safety and proper operation demand using only the adapter suggested by IBM. ... JD Hurst

Well Said! I second that

Perhaps I'm doing something wrong, as I simply plug mine in and get on with it.

jsmit86 wrote:

jhkaska wrote:I just checked the Targus brick that I bought a few months ago and it includes a sack of 8 various size connectors. One of them is identical to the connector on my t60p and has 20 stamped on the side. The brick is rated for 65W max on ac and 70W max on dc. The output voltage shows 15-24 but is not manually adjustable. So I guess that it automatically adjusts somehow. The model number is 800-0084-001A. Don't know if you can buy an individual connector from Targus but might be worth a try.

The #20 tip is listed for select Dell computers. The important thing to remember is that the tip actually adjusts the voltage of the adapter, so the connector may fit, but the voltage may be wrong.

I'd test the voltage first with the #20 tip, and see if it matches the Thinkpad adapter.

I am getting a new X60 and will run into the same problem, as I have a targus universal charger also. I am considering a modification of the charger using the #20 tip you describe. I'm guessing that one of the included tips outputs 20v, so I am planning to cannibalize the #20 tip and connect it to the other tip to get 20v through the large connector.

iGo has a power tip for X60/T60/T61, see http://www.igo.com/product.asp?sku=3024051. On the down side, it costs 10$ that you could also invest in the Lenovo charger (50$ total).

Volker wrote:iGo has a power tip for X60/T60/T61, see http://www.igo.com/product.asp?sku=3024051. On the down side, it costs 10$ that you could also invest in the Lenovo charger (50$ total).

Does this fit the targus adapter?

I don't have either AC adapter, but I'll speculate nevertheless. What are the chances of two competing companies agreeing on a powertip standard? Probably worse than the survival odds of a snowflake in hell

Volker wrote:I don't have either AC adapter, but I'll speculate nevertheless. What are the chances of two competing companies agreeing on a powertip standard? Probably worse than the survival odds of a snowflake in hell

Yes, you're probably right. i have noticed that they both use the same number 31 for the thinkpad compatible tips. it's a bit of a risk to take for the sake of a few dollars.

Volker wrote:.....What are the chances of two competing companies agreeing on a powertip standard? Probably worse than the survival odds of a snowflake in hell

Actually pretty good, since IGO (Mobility Electroncis) was the OEM manufacturer of Targus. (They also made these under the Kensington and IGO names)

Intriguing. I looked into that, and apparently Kensington really started out by selling rebranded iGo stuff. But the current crop, like the 120W model# 33197, have now different powertips. And of course there are no adaptors to plug the iGo tips into the new Kensington ac adapters.