Captive vs separate USB-C power supplies

y_p_w

y_p_w

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Just wondering what are the opinions on this. Apple currently only uses separate USB-C power adapters and a separate cable. The cables can be the latest USB-C to MagSafe 3 or just USB-C to USB-C, although the latter can be marked as higher current depending on the application, although any standards compliant USB-C cable should work with a minimum 3A/20V for 60W.

We have a Lenovo laptop that came with a 45W (Lenovo branded) power adapter with a captive cable. The actual manufacturer isn't listed. It was working for a few years but after a while it looks like the cable failed, and there's no practical means to replace just the cable as it's fused to the power adapter body. I've used a variety of different replacement power adapters including an Apple 30W with whatever cables I scrounged or bought, including some really cheap ones. I've also tried others. But it was kind of annoying that an OEM replacement was around the same price as a good quality USB-C power adapter and separate cable.

I did pay about $100 for a Chromebook that came with a 45W Lite-On USB-C power adapter with captive cable. I'm not quite sure how they managed to get that in the bill of materials, although I did buy the computer on sale. But unless they're really cheap, I'm not sure why most computers using USB-C don't come with separate power and cable, since the cables are generally the weak point.

I've actually been lucky with Apple's original MagSafe power adapters with a captive cable. I've have an original MagSafe cable from 2007 and it's still working. But I wonder how long. I've ended up patching mine with electrical tape when the jacket tore in a specific spot, but it otherwise looks like it's intact.
 
I like the Apple way of replacing the cheap cable rather than the expensive brick. The Belkin one I’m using now(on an Apple brick) seems to be holding up well.

Of course I still prefer MagSafe, which my first gen M1 MBP doesn’t have. Thankfully the current MagSafe implementation allows just the cable to be replaced too.
 
The best power adapters (including USB-C) and cables are made by Anker. The adapters based on Ga-N transistors run much cooler, and are more compact. Take a look at their product line. My set of charging cables and power cubes gets wrapped up and tossed in a bag daily. Anker is good quality gear.
 
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Astro14 said:
The best power adapters (including USB-C) and cables are made by Anker. The adapters based on Ga-N transistors run much cooler, and are more compact. Take a look at their product line. My set of charging cables and power cubes gets wrapped up and tossed in a bag daily. Anker is good quality gear.
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Agreed. I have Anker power supplies and wireless chargers as well, they are much better than any of the cheap junk you find. Very much recommend them.
 
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Astro14 said:
The best power adapters (including USB-C) and cables are made by Anker. The adapters based on Ga-N transistors run much cooler, and are more compact. Take a look at their product line. My set of charging cables and power cubes gets wrapped up and tossed in a bag daily. Anker is good quality gear.
Click to expand...
+1 for Anker AND their cables
 
Lenovo does still have regular laptop power supplies with removable cables although most if not all their laptops have switched over to USB-c, so I assume they're doing that as a cost cutting/standardization thing.

atikovi said:
What do you mean not compliant or unsafe? I'm using one right now to connect my new external drive to the computer.
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The converter you linked is not complaint with USB-C PD (power delivery.) Its akin to trying to run 1200watts through an 8 gauge wire. You also cannot charge-in with USB-A (I dont think, but USB-A doesn't carry enough power to charge a battery.
 
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Bailes1992 said:
I recently purchased a Xiaomi 12T pro that can charge at 120w. That comes with a separate plug and lead so it should be possible.
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120 watts? i know how charging curves work and that's only the peak input just for a moment but still. 120w going into a phone battery would give me a heart attack. I use a 500ma 2.5w charger that came with headphones since it slow charges my phone during the night while also using the adaptive charging thing so the battery doesn't get roasted. never fails to fully charge it and my battery health is at 99% after almost a year. Used to use the fast charger with my old Samsung and it fried the battery in just a year.

I wonder if that phone has a huge battery and like 4 or 6 individual cells to split the input c rating into more cells at once. I'm gonna have to research it. Had no idea you could pump that much power into a phone.
 
I remember reading an article several years ago about a google engineer discovering that a usb c cable without a 56k resistor fried an expensive laptop and that it's basically required when wanting to charge at a high input like 45w or more. But charging at like 30w or less doesn't require it for safety. that's really the only thing you should look for when buying a charger. I can see manufactures wanting to have the cable be captive to prevent you from buying a cheap c to c cable then frying the laptop. But in reality the charging controller on the device and power adapter if it's the smart type can test a cable first before figuring out how much power to send though it. But that requires smart circuitry which not everything has.
 
Pew said:
The converter you linked is not complaint with USB-C PD (power delivery.) Its akin to trying to run 1200watts through an 8 gauge wire. You also cannot charge-in with USB-A (I dont think, but USB-A doesn't carry enough power to charge a battery.
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I have it connected to a small external SSD. How much power can it use? 2 watts? What SHOULD I be using?
 
atikovi said:
I have it connected to a small external SSD. How much power can it use? 2 watts? What SHOULD I be using?
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You'll be fine because of the low power draw of your external SSD, probably like no more than 5w. YPW is trying to charge his laptop which is 45w at minimum.
 
Pew said:
You'll be fine because of the low power draw of your external SSD, probably like no more than 5w. YPW is trying to charge his laptop which is 45w at minimum.
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That device wouldn't work to even try to charge a laptop because it can only output 5V, and a 45w laptop won't charge on 5V. Probably needs 15V or 20V.
 
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atikovi said:
How can you even charge a laptop through USB? All the ones I've owned have a connector for a dedicated charging plug.
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Many newer laptops use a USB-C port for charging these days.

My Lenovo Yoga came with a standard large brick charger, but because the laptop power input port is USB-C, I was able to replace that brick with a small USB-C charger which is very convenient for travel. You just have to make sure the charger can deliver enough power and that you use a good enough cable that can handle it.

This is the one I use. It was on sale for $12.50 when I got it, cable included:
 
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