Power Connector

Over time, different ThinkPads have used different power connectors. You can use a higher Amperage rated power supply then your ThinkPad needs, as long as the physical connector is correct. But you should not use a lower Amperage power supply on a ThinkPad needing more Amperage. Doing so will overheat the power supply, and might cause issues such as screen flicker. Hint: In case you cannot find your Model ThinkPad listed, or you wish to double check, you can find the required power information on a label on the bottom of your ThinkPad NOTE! The Amperage's listed below are the OUTPUT values for the AC adapter, which should be equal or greater then what your ThinkPad requires All current Thinkpads require 20 Volt DC input. See also the official Lenovo page for power adapters.

6.3 mm outer, 3.0 mm inner diameter

Help needed

Will someone with an actual unit in-hand, please confirm the size?

15 V, 2.0 A Power.

• ThinkPad 350, 350C
• ThinkPad 500, 510CS
• ThinkPad 700T, 730T

4-Pin hexagon

NOTE!

The information found in this page is mostly correct. But the four-pin connector, in particular, is not thoroughly understood. This information is incomplete and not entirely correct.

4 pin power connector

Unknown watts/amps

• ThinkPad 355, 355CS, 355C
• ThinkPad 360, 360CS, 360C, 360P, 360CSE, 360CE
• ThinkPad 370C
• ThinkPad 700, 700C
• ThinkPad 720, 720C
• ThinkPad 750, 750CS, 750C, 750P

35W

AC Adapter PN 76H0119

• ThinkPad 755CX, 755CV, 755CD, 755CDV
• ThinkPad 760L, 760C, 760CD, 760EL, 760ELD, 760E, 760ED, 760XL, 760XD

40W

• ThinkPad 555BJ
• ThinkPad 755C, 755CS, 755CSE, 755CE
• ThinkPad 760LD

50W

20 V 2.5 A - FRU 49G2196

• ThinkPad 360PE
• ThinkPad 850, 851

56W

AC Adapter PN 12J2456

• ThinkPad 765L, 765D

Hint:

As these 4-pin PSUs are getting more rare and more expensive, a cheap solution if you don't have one is to adapt a universal 19-20V laptop PSU with a barrel connector. This isn't ideal if you're relying on the Thinkpad for some critical old business application, but it's fine if you're just a tinkerer playing with an old one off eBay for example.

Only the "+" and "-" connections (top-right and bottom-right looking into the connector on the back of the laptop from the back of the laptop) are required for basic operation, so that's all you need to adapt. Get an extension lead for your barrel connector - e.g. 2.1mm - and cut it in half. Discard the plug half. Get a "Mini JST" plug with flying leads, commonly used to power model helicopters etc. This is the plug that I've found will fit over the + and - pins. Wire the two together so that the red wire on the Mini JST is soldered to the centre contact wire on the barrel connector extension (socket half).

ALWAYS double check the polarity when plugging in your custom modded connector, since it's possible to get it the wrong way round.

4-Pin Kycon

This connector resembles, but is slightly larger, than Mini-Din.

120W power plug

120W 7.5 Amps

ThinkPad 120W AC Adapter (Support Website)
AC Adapter FRU PN 92P1035
AC Adapter Ouput: 7.5A, 16V

• ThinkPad G40, G41, G50
• ThinkPad Mini-Dock

5.5 mm outer, 2.5 mm inner diameter

16V coax connector

This is a 2.5/5.5mm barrel coax connector, delivering 16 volts.

35W 2.2 Amps

• ThinkPad 340CSE (rated 1.0A)
• ThinkPad 345CS, 345C
• ThinkPad 365CS, 365C, 365CSD, 365CD, 365E, 365ED, 365X, 365XD
• ThinkPad 380, 380D
• ThinkPad 560E, 560X, 560Z
• ThinkPad 560 (rated 1.9A)
• ThinkPad 701C, 701CS (rated 1.9A)

54W 3.36 Amps

Some of them have been recalled: see the page Damage in 56W AC-Adapter, plastic housing melted.

• ThinkPad 240, 240X, 240Z
• ThinkPad 390, 390E, 390X, i Series 1700 (i Series 1720, i Series 1721, i Series 1780, i Series 1781)
• ThinkPad 570, 570E
• ThinkPad i Series 1400 and 1500 (type 2621) (i Series 1400, i Series 1500)
• i Series 1200, i Series 1330
• ThinkPad T20, T21, T22

56W 3.5 Amps

• ThinkPad 235
• ThinkPad 340
• ThinkPad 380E, 380ED, 380XD, 380Z
• ThinkPad 385D, 385ED, 385XD
• ThinkPad 535, 535E
• ThinkPad 600, 600E, 600X
• ThinkPad 770, 770E, 770ED, 770X, 770Z
• ThinkPad TransNote
• ThinkPad X20, X21, X22, X23, X24, X30, X31, X32, X40, X41, X41 Tablet

72W 4.5 Amps

• ThinkPad A20m, A20p, A21e, A21m, A21p, A22e, A22m, A22p, A30, A30p, A31, A31p, A275, A285, A475, A485
• ThinkPad R30, R31, R32
• ThinkPad R40, R40e, R50, R50e, R50p, R51, R51e, R52
• ThinkPad T23, T30
• ThinkPad T40, T40p, T41, T41p, T42, T42p, T43, T43p

barrel connector, slim

19 Volt Coax connector
IBM called it "barrel connector, slim". 19 V, 45 W 2.4 A. 5.5 mm outer, 2.1 mm inner diameter. Option Marketing number 11J8702. See AC adapter matrix (Doc PD012162) as a source of information.

• ThinkPad 310 (type 2600)
• ThinkPad 310, 310D, 310E, 310ED
• ThinkPad i Series 1400 and 1500 (type 2611) (reference Doc LWIK-3Z7J5H)
  • i Series 1410, i Series 1411, i Series 1412, i Series 1450, i Series 1451, i Series 1452, i Series 1472
  • i Series 1512, i Series 1552

big barrel "advanced" connector

20V coax connector

20 Volt Coax. 7.5mm OD, 5.55mm ID, 0.8mm diameter central pin.

Signal Pin

Power controller subsystem senses when power is connected, and measures resistance between central signal pin and ground. Firmware policy might reduce performance (battery charges slowly, processors throttle to low speed) if an insufficient supply is detected. This issue is discussed at forum.thinkpads.com, "W520 requires 170W AC adapter".

power rating	resistance
65 W	10 kΩ
90 W	not connected
135 W	0 Ω
170 W	1.5 kΩ

Models using this connector

65W 3.25 Amps

AC Adapter Output 3.25A, 20V

• ThinkPad R60, R400, R500 - with Intel Graphics
• ThinkPad T60, T400, T400s, T410s, T500, T510, - with Intel Graphics
• ThinkPad T410i, T410si, T430i, T510i
• ThinkPad X60s, X61, X61s, X61 Tablet
• ThinkPad X100e, X200, X200s, X200 Tablet, X201, X201i, X201s, X201 Tablet, X300, X301
• Thinkpad Z60m, Z60t, Z61e, Z61m, Z61t - with Intel Graphics

90W 4.5 Amps

• ThinkPad R60, R60e
• ThinkPad T60, T60p, T61, T61p, T400, T410, T500, T510 - With ATI or Nvidia Graphics
• ThinkPad T430
• ThinkPad T520 - Dual Core
• ThinkPad W500
• ThinkPad Z60m, Z60t

135W 6.75 Amps

AC Adapter PN 55Y9317

• ThinkPad T520 - Quad Core
• ThinkPad W510

170W 8.5 Amps

AC Adapter PN 0A36227 (US) and PN 0A36231 (EU)

• ThinkPad W520
• ThinkPad W530

This AC adapter has the same diameter as the usual 20V AC adapters, but there is an extra plastic knob on one side of the connector. It is not round any more, that is, you can only plug it in one particular orientation. The extra knob prevents one from using the AC adapter on any other Thinkpads.

W700 Coax connector

6.0 mm outer, 3.0 mm inner diameter.

Help needed

Will someone with an actual unit in-hand, please confirm the size?

The W700/W700ds AC adapter plug has a different diameter than all other 20 Volt AC adapters. You cannot plug in a different AC adapter into a W700-series Thinkpad nor can you use the W700 AC adapter on a non-W700 Thinkpad.

170W 8.5 Amps for W700

AC Adapter PN 41R4421

• ThinkPad W700, W700ds

230W 11.5 Amps

AC Adapter PN 55Y9333

• ThinkPad W700, W700ds, W701, W701ds

slim tip

20V coax rectangle and barrel connectors

Lenovo wrote on store product description:

New rectangular fixed “slim tip” plug to support thin and light hardware designs

Lenovo introduced a new power connector in 2012. This connector is standard in all new models since late 2013 product line. It is rectangular, close in size to USB A connector, and it has a signal pin in centre. A conversion cable for 20V barrel plugs exists (ASM 0A36037; FRU 03X6261).

Signal Pin

power rating	resistance
45 W	120 Ω
65 W	280 Ω
90 W	550 Ω
135 W	1 kΩ
170 W	1.9 kΩ

Models using this connector

• OneLink connector
• ThinkPad Ultra Dock

45W 2.25 Amps

• IdeaPad Yoga 11
• ThinkPad Helix
• ThinkPad T431s
• ThinkPad X240s
• ThinkPad T440s (with Intel graphics)

65W 3.25 Amps

• IdeaPad Yoga 13
• ThinkPad Edge E531
• ThinkPad T440s (with discrete graphics)

90W 4.5 Amps

• ThinkPad X1 Carbon

135W 6.75 Amps

• ThinkPad T540p
• ThinkPad W540 (i5+K1100M)

170W 8.5 Amps

• ThinkPad W540 (i7+K2100M)

unsorted

• ThinkPad 820, 860, i Series 1124, i Series 1157, i Series 1300, i Series 1370, i Series 1620, i Series 1800
• ThinkPad S30, S31
• 54 or 56 W, clarity needed: i Series 1210, i Series 1230, i Series 1250, i Series 1260, i Series 1420, i Series 1460, i Series 1480, i Series 1421, i Series 1441, i Series 1422, i Series 1442, i Series 1482, i Series 1483, i Series 1492, i Series 1540, i Series 1541, i Series 1542, i Series 1560, i Series 1562, i Series 1592,

10.5 V, 1.0 A Power

• ThinkPad 220