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Kojo Eghan
Nobody can be exactly like me. Sometimes even I have trouble doing it.
Nobody can be exactly like me. Sometimes even I have trouble doing it.


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"The innovation in technology challenges us to think differently, and provide us a platform to solve the big issues in the world!" - Local Guide +Kim Flowers. More on Kim:
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According to the rumour mill, Apple may plan to use #USB #TypeC on their new iPhone 8. Hopefully the work of standards contributors (such as Google and Apple), certification laboratories, honorable third-party peripheral makers, and private individuals -- such as myself -- have helped "clean up" the #USBC space to the point users can purchase any product and use it without worry.

Obviously take this with a HUGE grain of salt, but I trust the WSJ did their due diligence.

(Once they get their chargers' power profiles sorted out, Apple would be very welcome in that last category! 😉)
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69th #USB #TypeC analysis: +CHOETECH "USB-IF Certified" USB 3.1 Gen 2 Type-C Cable [Model B01N8U9075 / A3002].
tl;dr: BAD cable. Another case of USB-IF doing a poor job of enforcing manufacturer-level quality control post-Certification.

This sample was provided by​ +Francisco Vigil from my queue of "USB-C Stuff to Analyze". So thank him for the test!

What I detail is based solely on findings from the "Fulfilled By Amazon" sample purchased by Francisco Vigil. The data is right here if you wish to verify.

[TotalPhase report for for Choetech B01N8U9075]

[TotalPhase summary sheet for 6 separate tests]

This cable failed signal integrity on EVERY run on the +Total Phase Advanced Cable Tester 2 at 10Ghz at default settings. This does not mean the cable doesn't meet compliance criteria -- it just means the cable failed a test every single other good cable in my section has passed.

This 1 meter "Gen2 10gbps cable" performs qualitatively WORSE than a 2m "Gen1 5gbps" Plugable Thunderbolt3 cable. Please see the attached image comparing two eye diagrams. This either means the Plugable is capable of 10gbps at 2m (extremely unlikely) or the Choetech cable has very poor cable stock (very likely) and operates at thresholds that +Intel would refuse to permit in their own cables.

There are major eMarker errors that by definition make this noncompliant. The CertStat field is blank. Vconn is marked as being required. Vendor ID and Product ID are blank. Therefore this is another demonstrable "BAD" cable certified by the USB-IF for sale to the public.

See my comments on the Targus "USB-IF Certified" cable here for the same criticisms:

Cable Termination Type
00b = VCONN not required.
01b = VCONN required
Cable Plugs that only support Discover Identity Commands SHALL set these bits to 00b Vendor ID
Manufacturers SHALL set the Vendor ID field to the value of the Vendor ID assigned to them by USB-IF. Product VDO
Manufacturers SHOULD set the USB Product ID field to a unique value identifying the product and should set the bcdDevice field to a version number relevant to the release version of the product. Cert Stat VDO
The Cert Stat VDO SHALL contain the XID assigned by USB-IF to the product before certification in binary format.
"Test lab engineers are required to confirm that the XID used in the cable under tests’ E-marker matches that which the USB-IF assigns. (If it doesn't match...) the E-marker tests are considered a Fail." Shall/Normative
Shall and Normative are equivalent keywords indicating a mandatory requirement. Designers are mandated to implement all such requirements to ensure interoperability with other compliant Devices.

Please also note +Brian Lowry 's report here regarding the cable failing immediately after purchase, sparking sounds, and causing errors to appear on his computer charge indicator:

"I purchased this cable and it in fact seems to have failed right out of the box. Furthermore, every time I try it on my Pixel, I cannot then seem to charge the phone with ANY other C-C cable until I reboot the phone. It also produces a discomforting crackling noise when I unplug the cable."

"Choetech is sending me a replacement cable as they are sure this must just be an isolated defect and seem adamant that the USB-IF certification is itself the pudding that proves. It does seem to work fine for others, including +German M. on his Pixel XL. But my laptop indicated a problem with it beginning with the very first use ('X' next to the battery indicator and no charge) and others have reported possible electrical crackling on disconnecting from a live power source. I'm also now consistently replicating the issue with my Pixel where I cannot use ANY known working C-C cables after I try the Choetech 10Gbps (with no success), until I finally reboot the phone. Only then will the phone again accept power from any of those cables."

End ramifications?

This cable will be less energy efficient and burn (5 volts)^2/(1k ohm) = 25mW of power it otherwise shouldn't on some "smart"/PD devices. Some devices may refuse to work with it if they demand a Certified cable. Some devices may get confused because of the 0000 VID and 0000 PID. (This is a non-valid entry.)

You be the one to tell Apple that you're draining their iPhone 8/iWatch 3 battery budget by 25mW due to a firmware bug with your cables, and see what happens!

I do not recommend this cable. It raises serious doubts about the USB-IF's commitment to their own stated rules. Am I missing something?

[Plus] Analyses Choetech B01N8U9075
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62nd #USB #TypeC analysis: +j5create "USB-IF Certified" USB3.1 Gen2 Type-C to Type-C Cable 3A/60W [Model JUCX03].
tl;dr: TERRIBLE cable. Does not work. Magic Control Techology should never have been USB-IF Certified. This is the fourth JUCX03 I've had in my possession that can't carry a signal. +Best Buy  needs to stop selling these, and the USB-IF needs to delist them. They are defective in an insidious manner that gives USB-C a bad name.

I implore the USB-IF to take this as a call to honor their stated mandate of protecting the tech ecosystem.

I bear no ill will to the USB-IF or Mr. Ravencraft, but these errors are significant and obvious. Almost to the point I think the manufacturer should lose privileges to use the Licensed USB-IF logo. I've brought this particular cable to their attention multiple times, as have their own testing laboratories.

Primary fault lies with "Magic Control Technology", the ODM. j5Create and Best Buy share secondary criticism for their inaction after multiple verified reports of bad cables; even if they lack the technical depth necessary to understand exactly what's wrong.

+Total Phase would like to highlight this as a reason to pursue every-cable testing at the manufacturer level. I however would like to highlight this as the need for independent, random sample purchase testing and auditing (ala SNELL motorcycle helmet safety certification).

It is MANDATORY to have feet on the ground, in stores, checking what customers are actually buying. Not a one-off "Golden Sample" sent by a factory. And if manufacturers violate that public trust -- they need to be held to task for it. This needs to be implemented in future Certification programs.

[TotalPhase report for j5Create JUCX03]

[TotalPhase summary sheet for 4 separate tests]

This cable has a number of failures. Primary of which, it simply won't work. Some won't work at all (no connection), some will work but fail when used (massive data corruption, or heat up).

+GTrusted found this out when their +Other World Computing, Inc. (OWC) Macbook dock wouldn't work at all because of eMarker problems. In total we tested three revisions (out of five) from Best Buy and none worked. (These were "blue box" versions: no USB-IF Sticker, but still claimed Certified per the roster.) GTrusted has additional privileged data they can contribute to corroborate my statement should they choose to do so.

+Total Phase found this out when I went to Best Buy and purchased a brand new, sealed cable and took it to their lab a month ago. (This was an "orange box" version, with USB-IF Certified sticker proudly displayed.) Again, this failed spectacularly on a number of measures -- and is in fact the cable I retain in my possession.

I've attempted contacting j5Create (and Best Buy) multiple times over the past few months, filing tickets in their systems, attempting to get them to fix their stock. But they have taken no action on this. This is why I so adamantly warn only to get the 5A JUCX01 cable, and not the 3A JUCX03.

The errors:

First, look at the cable box. It claims to be USB3.1 Gen2 ("Up to 10gbps"). The USB-IF trademarked license sticker says "SuperSpeed+ 10gbps Certified". The back says "Support USB 3.1 Gen 2 (10 Gbps), USB 3.0 (5Gbps), USB 2.0 (480mbps)".

Now take a look at the Signal Integrity charts from the TotalPhase Advanced Cable Tester Level 2 report at 10ghz. It can't maintain a signal in any of its SuperSpeed lanes. It's the absolute worst data cable I've ever tested by a wide margin.

Second, look at the pin resistances. Any single pin over 40mOhm is an instant fail. This has four -- on both plugs, on multiple pins. And all the rest are all bordering on failure. If you even used this only for charging, over time ALL of the pins will fail due to wear.

Third, look at the DC resistance. The GROUND wire is a fail. That's very, very bad since it also affects data signaling in addition to power. And keep in mind this is only a 3A cable, not even 5A with stricter thresholds!

Those super-thin +Anker 1m cords you can get are also rated for 3A, since that's the minimum USB-C current capacity. And the Anker manages to pass with flying colors! That's how bad the j5Create JUCX03 (or good the Anker A8181011) is.

Fourth, look at the "half speed" run. I had a hunch Magic Control Technology (j5Create's ODM) factory was doing "third shifts" and using inferior cable stock/connectors.

Seeing as how the Signal Integrity tests pass at 5ghz, I'm almost certain this is what happened. This is also confirmed by....

Fifth, a blatant violation of the USB-IF cable marking guidelines. Look at the ends of the connectors of the JUCX03 (bottom) compared to the JUCX01 (top). Notice how the JUCX01 has the proper "SS10 trident" logo for USB3.1Gen2, whereas the JUCX03 has the incorrect "SS trident" for USB3.1Gen1.

+Jen Warren and the folks at +Belkin take labeling issues like this extremely seriously. It is highly misleading for the consumer. In fact, Belkin even has a page dedicated to explaining this, since they are honest about such matters.

Per this document, the "USB-IF Certified" JUCX03 is a counterfeit. Except, it's not -- the USB-IF licensing division actually signed off on this cable. Twice, actually -- I've attached screenshots of the USB-IF "USB Type-C™ Certified Cables" document of both iterations  (blue and orange box).

Sixth, going down the list of violations, the eMarker is labeled as "Vconn Required" which is a violation of [Section Passive Cable VDO].

"Cable Termination Type: Cable Plugs that only support Discover Identity Commands SHALL set these bits to 00b. (00b = VCONN not required.)"

Seventh, the "Latency" (or Cable Length) field is Null/Zero. Meaning they forgot to fill it in. This is another [ Passive Cable VDO] violation.

"Cable Latency: 0000b – Reserved , SHALL not be used"

I'm certain there's additional errors that I'm not even catching, forest for the trees, but this is an absolute horror show. I want my $30 bucks and time writing this up back!

And if anyone believes I am being slanted, please keep in mind I think the 5A JUCX01 is a fine cable. But this 3A JUCX03 is so terrible I'm actively seeking a replacement for the JUCX01 cable to recommend simply so I can delist j5Create altogether. As I have found myself in the odd position of public watchdog, as +Benson Leung has, I have to occasionally bite.

[Plus] Analyses j5Create JUCX03 v2
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It has been "very difficult and very hard" to ensure that consumers get exactly what they believe they're paying for.
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59th #USB #TypeC analysis: +CHOETECH 55W Multi-Port USB Charger with USB-C Ports [Model TC42C].
tl;dr: Noncompliant AND unsafe. Turns on inappropriately with eMarked cables (like our old friend the Nexus 6P OEM charger). Has NO overcurrent protection -- I was able to max out my load testers at 6A on any/all of the ports. No IR drop compensation either. Included USB2.0 C-C cable is OK. This is an 11A-rated short waiting to happen!

This sample was provided by +Liviu Sas from my queue of "USB-C Stuff to Analyze". So thank him for the test!

This fault I didn't expect to see again -- yet here it is. This charger has the same class of failure as the original Nexus 6P OEM charger I cited way back in July on Reddit.

The Choetech turns on when any pulldown resistor is applied to the CC line to 2.44-0.0V. These thresholds are incorrect. (It must be 2.6v-.85v.) This means eMarked/USB3.1 cables with a 1k Ra pulldown will "trick" this charger into outputting current inappropriately. This also means it is functionally a Vbus HOT receptacle charger, when using eMarked cords -- one of my instant-fail conditions.

Note this is the same class of failure as the original Nexus 6P OEM charger (which turned on from 2.6v-.20v). However, this Choetech takes that mistake one step further: Choetech turns it on all the way down to 0.0v. This means a simple CC short circuit, such as a pinched cord -- or even a USB-C 3.5mm headphone adapter -- will be enough to force the power supply on. This is super-bad and unsafe, especially now that eMarked cables are the norm.

Typically, receptacle chargers should only turn on when a 5.1k Rd resistor is present. (The end-result CC voltage should be higher, at 1.60v nominally.) Here's the Twinkie log showing the Chotech failing compliance:

> tw cc
CC1 = 2989 mV ; CC2 = 2960 mV
> tw vbus
VBUS = 1 mV ; 0 mA
(port is off, no resistor connected)
> tw res ra 0
> tw cc
CC1 = 322 mV ; CC2 = 2961 mV
> tw vbus
VBUS = 5125 mV ; 51 mA
(port turns in inappropriately with just Ra!)
> tw res 0 0
> tw res 0 rd
> tw cc
CC1 = 2989 mV ; CC2 = 1626 mV
(THIS is the proper level it should turn on at.)
> tw vbus
VBUS = 5126 mV ; 50 mA

Compounding this "Vbus HOT with USB3.1 cords" problem, there is absolutely no individual port overload protection whatsoever. I was able to max out both my load testers on a single port -- with no Rd present, mind you.

This is again incredibly unsafe. Merely leaving your Apple Macbook charge cord plugged into this charger means a pet chewing on it/the cable gets caught in a door and shorted will zapped by up to get up to 6-11A*5V=30-60W of heat. This is a fire hazard. (On proper, safe, compliant supplies, the cable is not powered until a device is connected first. And even if caught in a door, overcurrent will shut the individual port off.)

The charger doesn't properly fully isolate Vbus from the Type-C outputs using two FETs back to back. (At least it seems to isolate/float CC... since it doesn't pretend to be a device when connected to the Pixel unpowered.)

These combination of errors means I can do some really wacky nonsense -- like shown in the third picture. I can backfeed current from the Nexus 6P OEM charger -- INTO the Choetech charger -- through a USB3.1/eMarked with no Rd --  then back out the Type-A ports -- and then load it to 3A. This picture is so wrong, it gives me a headache. This is not how Type-C is supposed to work!!

Finally, the Type-C ports have BC1.2 DCP signaling (D+/D- shorted) and the Type-A ports have Apple 12w signaling (2.7v). But no IR drop compensation means voltage sags -- sometimes excessively. The  included USB2.0 C-C cable is "okay". But quality is a bit of a crapshoot, per my TC0001 cable test.

[TotalPhase report for for Choetech TC42C cable]
[TotalPhase report (120% SI) for for Choetech TC42C cable]

[TotalPhase summary sheet for 5 separate tests]

All in all I think this charger is a fire hazard waiting to happen, so I am giving it my lowest rating despite it "technically" being switched Vbus cold.

11A is a HUGE amount of current! And I've demonstrated this charger has no overload protections. That alone makes it 1-2 tiers worse than the Nexus 6P OEM, which at least has proper overcurrent protection, and only turns on above .20v -- NOT a dead-short of CC. A cable caught in a door /under a chair will cause such a dead short across CC line, turning the Choetech's 11A on!

I strongly suggest +Choetech Official consider recalling this and exchanging it for a corrected model, given the propensity for high-power shorts with long eMarked charging cables (like included with the Macbook Pro 2016). I suggest people discontinue use of this charge station when able, and return or exchange it for a refund, or safe/compliant model.

(The Anker PowerPort5+ 60W with USB-PD is an example of one with such safeties. Please note I cannot recommend the PowerPort 40w non-PD model, due to user reports of that having other design faults.)

[Plus] Analyses Choetech TC42C
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[Study] This is a followup to the post where I discovered the Pixel/Sailfish was only charging at 5v/3a=15W max. By using the noncompliant Apple 87w adapter (which only offers 5v/2.4a=12w), the Sailfish is FORCED to charge at the 9v/2a=18W profile. Below is data from an experiment in this "anomalous state" emulating my previous study.

[Previous Pixel/Sailfish study (5v/3a on OEM 18W charger)]
[Previous Nexus 6P/Angler study (5v/3a on OEM 15W charger)]

Please note I've added some extra diagnostic fields -- namely, I can now actually measure the current routed from within the phone to the battery!

Basically, this means I can separate the physical power entering the phone from the Type-C port (Vbus USB-C) from the internal converted battery being fed to the cells (Battery voltage). This lets me see the actual conversion efficiency of the Buck-Boost circuit inside the phone. Neat!

Per my data, you are losing <2 watts in the conversion. Also note the thermals are actually BETTER than 5v/3a charging. This seems to disprove the patch note HTC made regarding the decision to lock out 9v/2a charging!

However, this may also be an artifact of the ambient temperature being much colder now (Jan 1st) than when I ran the last experiment (Nov 1st) -- or the fact I am having to cut down on my heating bills because of finances. :(

For additional details, such as "how much faster it charges at 9v/2a versus 5v/3a", or "charging current profile differences", please compare the data in this post to that of the previous post.

9v/2a: 16% to 100% in 1:41
5v/3a: 16% to 100% in 1:35

Note about the "symmetric" looking Twinkie Vbus/Current graph: this is the result of the Apple 87w charger lacking linear IR drop compensation. As current draw goes up, voltage goes (marginally) down. Keep in mind the Voltage axis minimum on the graph is not Zero... you are merely seeing Vbus vary (marginally) around 9v.

#USB #TypeC #USBC #madebygoogle #anyonehiring ?
[Plus] Analyses Sailfish-PD 9v
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58th #USB #TypeC analysis: +CHOETECH 5V/3A 15W Type-C Wall Charger with cable [Model TC0001].
tl;dr: VERY BAD. Charger is Vbus HOT (instant fail). Cable out-of-spec (fails DCR). No IR drop compensation (sags voltage), so devices will charge slowly. Pretends to be a device when unplugged, causing the Pixel to backfeed current. The only good thing is the overcurrent behavior. Choetech needs to stop selling this.

This sample was provided by​ Reddit user /u/mww42 from my queue of "USB-C Stuff to Analyze". So thank him for the test! 
"(...) This is ranked very highly by Amazon -- but as I've shown in the past, you can't really trust Amazon's star ratings for engineering safety."

Well, that was fast. This charger is an instant fail. And I proved my point once again -- you can't trust Amazon for engineering safety.

The Choetech has a "Vbus HOT" receptacle -- meaning it doesn't look for the presence of a device [5.1k Rd pulldown resistor] before outputting 5v/3a. This allows you to unsafely bridge two power supplies together with a C-to-C or A-to-C cable. It also makes the charger more prone to shorting out due to debris/during cable insertion. Do not pass go, do not collect $200.

Choetech saved maybe... $.20 cents?... per unit omitting the comparators and MOSFET necessary to be safe and USB-C Spec v1.2 compliant. As a result, you have a highly unsafe charger that may potentially damage your device, cable, computer, or other charger. Oddly unlike most Vbus HOT designs I've seen, Choetech actually remembered to put in the "3a" signal Rp resistor. Which probably explains why people missed this major safety oversight for so long.

[TotalPhase report for for Choetech TC0001 cable]
[TotalPhase report (120% SI) for for Choetech TC0001 cable]

[TotalPhase summary sheet for 5 separate tests] (<- failed 100% of the time)

The included Choetech cable also is not USB-C compliant. Almost every pin resistance value violates the DC Resistance requirements in the spec, per the +Total Phase Advanced Cable Tester Level 2 at my disposal.

Please note the values mandated in the spec are absolute maximums. It falls to manufacturers to make sure their products are safely inside of that. ("Safety factor.") This cable is an example of what happens when a product is blueprinted with a SF of "1". (Please note connectors wear out!! The resistance can only go UP with time. Note the "insertion count" on the ACT2 output.)

The cable passes (quite well actually) on TOTAL resistance, but not PIN resistance. This pin requirement is for safety, in case one or more pins don't make good contact. This will potentially cause ground signal issues, or worst case [unlikely but possible] will melt the connector due to the resistance spiking.

There are 4 pins for Vbus and 4 pins for Ground on each side -- resistance is calculated in parallel. [1/(1/A + 1/B + 1/C + 1/D) = total pin resistance.]  Pin resistance of plug 1 + Wire resistance + Pin resistance of plug 2 = Total resistance... of ONLY Vbus or Ground. If one element fails, it's tolerable. If two or more elements fail, it's much, much worse. [40mOhm/4=10mOhm. 40/3=13.33. 40/2=20. 40/1=40.]

This also tells me Choetech had to use a MUCH thicker wire than they needed to in order to keep the total DCR in check, rather than sorting out the resistance problem in their paddlecard connectors. So their engineers didn't budget their tolerances properly. (This engineering oversight likely actually cost them money, in addition to making the cable noncompliant.)

So in my opinion: this Choetech cable -- which has pin resistances that are all at-or-above the maximum USB-C spec thresholds when BRAND NEW, is unsafe to use long-term.

Additionally, the charger lacks IR drop compensation whatsoever. The voltage sags to fairly low levels. I noted voltage dipped to 4.6v@3a[cable end w/ Choetech cable] 4.96v@3a[charger end]. Please note this is perfectly within USB-C spec of 4.0v@3a[cable end] 4.75v@3a[charger end].

IR drop compensation is an OPTIONAL, but highly recommended feature that keeps voltage output flat across at loads. Without it, some noncompliant devices like the Pixel/Nexus 6P will not charge. From my experience, it won't charge beyond a point at which voltage sags below 4.95v. Looking at the excel graph, this happens at a max current of 1.5a.

This means this charger+cable will only charge a Pixel/Nexus 6P at 1.5a despite saying "charging rapidly". (The "Charging rapidly" message is based off the Rp advertisement, not the actual current draw.)

The charger has BC1.2 DCP signaling (D+/D- pins bridged). This is fine per the spec. But as I cited previously, It is my opinion that it is wise to use an Autocoding chip so legacy devices (like Apple iPads with C-to-Lightning) will charge rapidly.

The overcurrent protection is actually decent. It sags to 4.0v (the lowest permitted in the USB-C spec) then cuts power. On the downside, power is restored almost immediately -- so it keeps cycling rapidly. I'd prefer it stayed off until the cable was unplugged / replugged manually. Still, this is a LOT better than some other products. (But being Vbus HOT means this is moot! Forest for the trees.)

All in all, in my OPINION, this charger (and cable) is quite unsafe to use. +Choetech Official needs to pull this charger from the market and create a fixed version (a) Vbus cold, with a MOSFET switching Vbus based on the CC line voltage and (b) fix their cable's paddlecard resistances. If you are using this, please discontinue use at your first convenience. Vbus HOT is one of the biggest failures a charger can have short of outputting the wrong voltage.
I am very concerned since this seems to be the exact same cable included with the OTHER Choetech product I have, a 55w charging station!

(Edit:) I just tested and found it also falsely pretends to be a device when connected to a Google Pixel alone, causing the Pixel to backfeed current into an unconnected charger! :(

[Plus] Analyses Choetech TC0001
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PSA: Please NEVER attempt charging your #madebygoogle Pixel like this. You will possibly damage it. USB male-A-male-A cords are illegal and shouldn't be used*, especially not like this with an OTG ("legacy device") dongle.

You'll trick the Pixel and Power brick into slamming voltages against each other.... not good. Depending on the order it's plugged in, you may damage a chip inside the phone.

#USB #TypeC   #USBC
*(Except for professionals and power users.)
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