USB-C to older connectors (barrel, Lenovo slim-tip, etc.)

[Yotsuko]

Using USB-C cables and chargers with older style connectors is something I've actually been curious about for a little while and in this video from Laptop Retrospective, such cables are covered.  Now on the two computers shown in the video, it's seen that this is possible.  However, I'm wanting to see how well it works with some more demanding systems, such as the Dell G15.  So I have a USB-C to 7.4mm Dell barrel cable that should be arriving tomorrow.  While the Dell G15 comes with a 170W power brick, it does seem to get along well enough with a lower wattage adapter.  I'll be trying the cable with an 87W Platinum-branded USB-C power adapter, which saw regular use with my 16-inch MacBook Pro.  Hopefully the results are good.
 

 

[saturnotaku]

This is intriguing as there are several laptops I've been interested in but dismissed because they don't support USB-C charging. 

[Steerpike]

This is fascinating!  I have a few old Samsung Laptops I'd like to 'adapt' to my new USB-C chargers, and especially with my new USB-C battery power banks. 

 

I couldn't figure out how this could possibly work, since USB-C power delivery is a 'negotiated' system, with the source starting out at 5V, then negotiating all the way up to 20V; but then one of the comments in that Lenovo Laptop youtube video says "Basically these cables have PD decoy chip hidden in one of the connectors which asks the PD charger for a set voltage.
So instead of having smart communication between the charger and the charged device as you normally do with PD devices, here you will get 20V at the end of the cable the instant you connect it to the PD charger."

 

So now I need to see if someone is making these cables for laptops other than Lenovo! Can you tell us where you got the Dell variant of this cable from?

 

FYI, I posted a bunch of info about USB-C PD in another thread in this 'Accessories' area. I'm not sure how to link to a specific post, so here's the 'meat' of the post for reference: 

 

From that post: 

====================================

1. 'Type-C only' - The USB Type-C specification allows for up to 15 Watts of power to be transferred from DFP to UFP on the VBUS and Ground signals.  This 15 Watts of power can only be transmitted at 5 Volts when a “Type-C Only” solution is used. 
2. 'Type-C PD' - When you add the USB Power Delivery specification to a “Type-C Only” system, you create a “Type-C PD” system and can raise the VBUS voltage above 5 Volts to a maximum of 20 Volts and raise the VBUS current to a maximum of 5 Amps.

 

But I think this latter category - Type-C PD - has two sub-categories - with or without the EMCA. If the cable doesn't have an EMCA chip, it is limited to 3A (but can still go up to 20 V, and thus, has a max power of 20x3=60W). If you add the EMCA, you can now go to 5A, which means the max power is 20x5=100W.

 

This is confirmed in this article: WHAT THE TECH? USB-C AND POWER DELIVERY EXPLAINED – Goal Zero - "Power Delivery starts at the 5V setting and is configurable up to 20V. Using a standard USB-C cable, it can handle up to 60W, and will go up to 100W using a designated EMCA cable."

 

====================================

I'm now going to look for those cables for my Samsung and possibly even Dell laptops ....

 

Update - promising Amazon link - Amazon.com: Cablecc USB 3.1 Type C USB-C to DC 4.5x3.0mm Adapter PD Emulator Trigger 90 Degree Angled : Electronics - have multiple barrel sizes. Need to figure out the size of my old Samsung laptop ...

[John Ratsey]

34 minutes ago, Steerpike said:

 I'm not sure how to link to a specific post, so here's the 'meat' of the post for reference:

I've figured that out: Click on the 3 dots at the top right of a post and one of the options is "Share". Select that and then copy the link.

[Steerpike]

2 hours ago, John Ratsey said:

I've figured that out: Click on the 3 dots at the top right of a post and one of the options is "Share". Select that and then copy the link.

Duh!  I saw that but only glanced quickly. I thought it was only intended to let me 'share' on Farcebook, Twatter, etc - which I avoid like the plague! 

 

I've ordered a 3.0 x 1.1 mm 'USB-C PD' adapter, and I'll see if I can charge my old Samsung NP940X5j with it (from my new USB-C PD chargers)!  The official spec for the old Samsung is 19V, but I suspect / hope that 20V won't cause it too much concern. Actually, looking at the order page again, I see that it shows '19V' on it - 

Amazon.com: Cablecc USB 3.1 Type C USB-C to DC 20V 3.0x1.1mm Adapter PD Emulator Trigger 90 Degree Angled : Electronics

 

I recently invested in a few extra USB-C PD chargers, and two USB-C PD battery packs. The battery pack is great - it tells you the Voltage, current, and 'time remaining' while charging the laptop, so I can get info that Battery Info View can't give me (once charged). 

[Reciever]

Very interesting, thanks for sharing :) 

[Steerpike]

I received the item linked above - https://www.amazon.com/dp/B07SJ3GQTD?smid=A2OKSEIX7OEK0B&ref_=chk_typ_imgToDp&th=1 for use with my 2014 Samsung NP940X5J, which has a proprietary 19V / 2.37A 45W power supply with a 3.0 x 1.1mm tip.  The good news is, the adapter works with my LG Gram 65W USB-C PD power supply (that came with my LG Gram 17). But it does not work with my Anker 65W USB-C PD power supply, which works fine with the LG Gram laptop, and charges my Samsung S10+ phone.  And it does not work with my Samsung 65W USB-C PD power supply (that shipped with my new Samsung NP950XDB).  When I plug the adapter+Anker PSU or Samsung PSU into the old Samsung laptop, the battery status briefly changes to show a charger, then within a second, changes back to indicating battery. So it 'almost' works, but not quite!  

 

Strangely, the adapter also works with my two external 100W USB-C PD 20Ah battery packs from BaseUS - so the odd items out are the Anker PSU and the Samsung PSU!  But that Anker PSU and that Samsung PSU work fine with the two battery packs, and with my new Samsung NP950XDB laptop. 

 

Device                  LG Gram     Samsung     BaseUS          Old Samsung
                        USB-C PD    USB-C PD    USB-CD PD       Laptop
                        Laptop      Laptop      Battery pack    (with Adapter)
Charger		
LG Gram USB-C PD        Works       Works       Works           Works
Samsung USB-C PD        Works       Works       Works           Fails
Anker USB-C PD          Works       Works       Works           Fails
BaseUS USB-C PD Battery Works       Works       n/a             Works

 

The device was very cheap. I may just try buying another brand from Amazon and see how that works.  But at least I can charge the laptop using my external battery packs, and one of the wall chargers, so I have a functioning solution for now. 

[John Ratsey]

Thanks for this useful research. There's clearly some variation in the implementation of the USB PD standards.  I briefly wondered if not all the chargers support 20V but I checked my Samsung 65W USB-C  PSU and 20V is listed.

[Steerpike]

10 hours ago, John Ratsey said:

Thanks for this useful research. There's clearly some variation in the implementation of the USB PD standards.  I briefly wondered if not all the chargers support 20V but I checked my Samsung 65W USB-C  PSU and 20V is listed.

Can you elaborate on what you mean? If you look on the back of your Samsung laptop (the new one, that is USB-C PD chargeable) it says "Input: 20V 3.25A (65W)" (at least, mine does!), so that would make it somewhat 'required' that the PSU would support 20V. 

 

I presume you've found yourself using your Samsung charger with your LG laptop, and your LG charger with your Samsung laptop?  The 'standardization' of PSUs was one of the biggest incentives to go with these new laptops.

The new Samsung charger that came with my laptop is ridiculously small!  And it's 65W, which means it's capable of supplying my LG Gram 17 - so that's going to be the one I travel with, I suspect. 

 

Interestingly, while the LG Gram 17 PSU/charger mentions USB-C PD, the Samsung does not!  These are the two chargers:

 

 

Note the LG says: "Output: 20.0V / 3.25A, MAX 65.0W (USB-PD) 5.0V / 3.0A 15.0W or 9.0V / 3.0A 27.0W or 15.0V / 3.0A 45.0 W"

and the Samsung says: "Output: (PDO) 5.0V / 3.0A or 9.0V / 3.0A or 15.0V / 3.0A or 20.0V / 3.25A (PPS) 4.0-20.0V / 3.25A"

(not sure what PDO and PPS mean; it does have the graphic, lower right, saying 'Certified USB Fast Charger 65W).

 

This article confirms that PPS is a part of the USB-PD specification. "The second specification—PD 3.0—includes programmable power supply (PPS), a feature that allows the USB Type-C charger’s output voltage to be adjusted in increments as small as 20 mV over voltages ranging from 3.3 to 21V". The article also tells us that 'PDO' is 'power delivery object' and relates to the communications between the PSU and device. 

 

I took a picture of my three USB-C PD PSU / Chargers just for grins ...

 

 

 All three are 65W; the third is an 'Anker' brand. The Samsung is the thinnest, the Anker is the shortest. This is how small the Samsung is ...

 

 

Not bad for a charger than can handle a laptop and a phone!  By the way - they do get very hot when delivering the 3.25 A! 

[John Ratsey]

1 hour ago, Steerpike said:

Can you elaborate on what you mean? If you look on the back of your Samsung laptop (the new one, that is USB-C PD chargeable) it says "Input: 20V 3.25A (65W)" (at least, mine does!), so that would make it somewhat 'required' that the PSU would support 20V.

I didn't look on the bottom of the computer but did check the small print on the Samsung charger (which (UK version) is bigger than yours but still a lot smaller than the LG PSU. Your discovery of PPS provides a possible clue. What happens if the Samsung PSU supports PPS? Does it produce the nominal 19V wanted by the adapter but the computer actually wants a bit more than 19V to be happy while a non-PPS charger produces 20V which the computer is happy to accept although it's more than the voltage on the label?

 

BTW, when I'm travelling I normally take a 45W charger as it's smaller than my Samsung 65W charger. The computer will give a warning when the charger is plugged in but then gets on with the job. The lower rating means that it can't charge the battery at the maximum possible rate when the computer is running. I've even used a 25W charger.

[Steerpike]

6 hours ago, John Ratsey said:

...

 

BTW, when I'm travelling I normally take a 45W charger as it's smaller than my Samsung 65W charger. The computer will give a warning when the charger is plugged in but then gets on with the job. The lower rating means that it can't charge the battery at the maximum possible rate when the computer is running. I've even used a 25W charger.

What 45W charger did you buy?  I'm traveling in 10 days for 2 weeks (first proper trip since pre-2020!), part of the justification for buying the Samsung.  I presume a 45W charger will be even smaller than the 65W guy, which is getting ridiculous! They're going to start falling through the holes in my bags! 

[John Ratsey]

4 hours ago, Steerpike said:

What 45W charger did you buy?  I'm traveling in 10 days for 2 weeks (first proper trip since pre-2020!), part of the justification for buying the Samsung.  I presume a 45W charger will be even smaller than the 65W guy, which is getting ridiculous! They're going to start falling through the holes in my bags! 

Mine is the Samsung 45W phone charger https://www.amazon.co.uk/Samsung-Official-Super-Charger-Cable-Black/dp/B09PWHYSH8 . However, I'm not sure if it's much smaller than your 65W charger (the length of my Samsung 65W PSU is 2 1/4"). I've also got this very compact Juice charger https://www.amazon.co.uk/Juice-EVERYTHING-charging-Smartphones-Technology-Black/dp/B092DZS3XR which claims to be 65W (but is maximum 45W from the USB-C port) and usefully has a USB-A port for charging other devices. I've had no problem with mine but see that some people have had failures. I carry a 25W USB-C charger in the bag for emergencies.

[Steerpike]

10 hours ago, John Ratsey said:

Mine is the Samsung 45W phone charger https://www.amazon.co.uk/Samsung-Official-Super-Charger-Cable-Black/dp/B09PWHYSH8 . However, I'm not sure if it's much smaller than your 65W charger (the length of my Samsung 65W PSU is 2 1/4"). I've also got this very compact Juice charger https://www.amazon.co.uk/Juice-EVERYTHING-charging-Smartphones-Technology-Black/dp/B092DZS3XR which claims to be 65W (but is maximum 45W from the USB-C port) and usefully has a USB-A port for charging other devices. I've had no problem with mine but see that some people have had failures. I carry a 25W USB-C charger in the bag for emergencies.

Website gives package dimensions but not product dimensions!  My Samsung 65W charger is 2" x 1 7/8" x 1 1/8" or 50mm x 48mm x 28mm, which sounds smaller than yours!  Amazing. 

[John Ratsey]

3 hours ago, Steerpike said:

Website gives package dimensions but not product dimensions!  My Samsung 65W charger is 2" x 1 7/8" x 1 1/8" or 50mm x 48mm x 28mm, which sounds smaller than yours!  Amazing. 

We've wandered off topic here but (i) my UK Samsung 65W PSU is 56mm (excluding the prongs) x 46mm x 27mm and a Samsung European 45W PSU is 50mm (main body) / 68mm (including smaller part to fit some sockets) x 52mm x 28mm (so it's not as small as I thought). The labels on both mention PDO and PPS.