USB car charger for phone: description, reviews and photos. Why is my car USB adapter slow to charge my iPhone? Autopsy check

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Car USB charger for phones, navigators or recorders. It would seem that what could be simpler?! However, the charger in the cigarette lighter may have, in addition to the main one, a number of additional useful functions. Let's test a few of these gadgets and evaluate their usefulness!

Charging, but not only

Popular Chinese online trading platforms offer a huge selection of USB devices for charging gadgets in the car. Some time ago, “Wheels” spent time trying to understand whether it is possible to get nickels with the proverbial penny?

It turned out that it was impossible: despite the powerful charging current of two, three or more amperes stated on the case, none of the cheap chargers could provide even one ampere. This time we decided to turn to a range of chargers that have a range of additional functions, and we test three devices that seemed the most interesting to us.

Device No. 1

Cost - 182 rubles

Structurally, it is the simplest adapter for the cigarette lighter connector. It has two USB sockets, promises a current of 3.1 amperes, plus has a built-in voltmeter, ammeter and even a thermometer! While the USB cable is not inserted into the charger, the display alternately shows the on-board voltage and the ambient temperature. When a USB consumer is connected, its current is in amperes.

Device No. 2

Cost - 317 rubles

Structurally, it is also an adapter for the cigarette lighter connector, but with adjustment of the bend of the “leg”. A current of as much as 3.4 amperes is promised for two USB sockets. The display always shows only the voltage of the on-board network, the current consumption via USB does not show, there is no thermometer. But there is an audible alarm for an emergency low voltage in the on-board network!

Device No. 3

Cost - 575 rubles

Structurally, a glass is installed in a standard interior cup holder and connected to the cigarette lighter socket with a short cord. It has two 3.1 ampere USB sockets, a splitter for two cigarette lighter sockets, as well as two buttons that turn off the cigarette lighter sockets without pulling out the plugs from the connectors. When the cord is not inserted into the charger, the display alternates between the on-board voltage and the voltage at the USB output. When a USB consumer is connected, its current is in amperes.

Operation of additional functions

All three devices can work as a voltmeter. This useful feature, since on most modern cars A digital, or even more so a dial voltmeter, is a rarity. In case of serious problems in the car's electrical network, of course, the warning light will come on, but a full-fledged voltmeter will allow you to track, for example, the unpleasant tendency of the battery to be undercharged due to low voltage at idle speed in traffic jams with powerful consumers turned on, and even the beginning of battery failure It will also help to notice the control unit in the generator.

How accurate are the voltmeters in our chargers? We connect them to a current source along with a control voltmeter. With 13 volts at the input, the first device gave a decent error of 0.4 volts, the second - an insignificant 0.1 volt, and only the third was flawless.

Not all gadgets have audio control over the voltage drop in the on-board network; of our samples, only the second device has such a talent. When the voltage drops to 11.5 volts, it begins to emit a loud intermittent squeak - very convenient, because you can’t always keep track of the display! Plus, the red word “LOW” lights up on the screen.

The ability to measure the air temperature inside the car was present in only one device out of three. Oddly enough, in the cheapest and frailest - No. 1. The function is only partially functional: the temperature readings are correct as long as the device is not used as a charger. As soon as it starts to heat up from charging the phone battery, the built-in temperature sensor begins to perceive the temperature of the charger case, and not the temperature in the car interior.

Charger No. 3 is interesting because it is the only one of all three that shows not only the onboard voltage, but also the USB output voltage. This information is quite useful: by the voltage drop on the 5-volt output, you can track the charger overload. If it produces 4.8 to 5 volts under load, then charging in progress. If the voltage drops below these limits, this means that the charger cannot cope - the phone will take a very long time to charge, and the device itself will overheat with the risk of failure!

In addition, this same device is also a cigarette lighter splitter, which is useful when you need to turn on several consumers, some of which are powered by USB, and some by 12 volts (for example, a DVR and heated seats). Each of the two sockets of the splitter is turned on with its own button to disconnect consumers without pulling out their plugs.

Work as a charger

Well, now, actually, the most important thing: let’s find out how our subjects perform the main task of charging a mobile device! Let's connect a voltmeter, an ammeter and a load to them and see what maximum output current they will produce until the voltage of 5 volts begins to dangerously sag. And compare the result with the current that is promised.

First, let's load chargers into a 5 ohm resistor, which should provide an output current of 1 ampere:

Device No. 1

The voltage dropped to 4.7 volts. By the way, the device indicator is lying: it showed a current of 1.33 amperes, although the external ammeter did not agree: the real current is 0.94 amperes! Very mediocre, but, in principle, functional.

Device No. 2

The voltage dropped to 4.8 volts. The device indicator cannot show current, but the external ammeter shows 0.99 amperes. Compared to the promised 3.4 amperes, this is clearly rather weak... In general, it’s tolerable and can be used.

Device No. 3

The voltage dropped to 4.9 volts. The device indicator shows a current of 1 ampere, and the external ammeter also shows 1 ampere. So far everything is fair, but the test, I must say, is childish...

Let us remind you that all devices have a stated charging current higher than 3 amperes... There is little optimism, as in any test of Chinese auto gadgets, so let’s try to squeeze at least two amperes out of them, now loading them onto a 2.5 Ohm resistor:

Device No. 1

The current is 1.65 amperes in the load, and the voltage has dropped to an unacceptable 4 volts. Obviously, 1 ampere is the limit for this charger (although, remember, 3.1 amperes are promised!).
It’s a little weak, but you can use it – for example, for smartphones with a small battery capacity or for a DVR. At the same time, it’s unlikely...

Device No. 2

At 1.8 amperes at load, the voltage dropped to 4.5 volts. Obviously, 1.5 amperes is a reasonable limit for this charger (although, remember, 3.4 amperes were promised!)

Suitable for charging most smartphones; with some charging slowdown, you can also power a DVR or similar gadget in parallel.

Device No. 3

At 1.8 amperes at load, the voltage also dropped to 4.5 volts. Despite the large dimensions of the “glass” and the promised 3.1 amps, the Chinese skimped on the powerful filling; 1.5 amperes is a reasonable limit for this charger. Similar to the previous device, it is suitable for charging most smartphones, and with some slowdown in charging, you can also power the DVR in parallel.

your gadgets using a USB tester. We present to your attention another method that does not require any additional equipment.

Modern smartphones and phones provide their own charging by controlling the level of charging voltage, charging current, battery voltage and its temperature. The phone knows all this data and can show it to its owner in service mode. It is also called engineering, factory or test.

Attention! If you are unsure of your actions, please do not enter your phone number into service mode. There are rumors that someone somehow managed to ruin their device in the process.

And for those who are confident and not afraid, we continue.

For the purity of the experiment, we switch our phone to “airplane” mode (so that its charging consumption does not fluctuate depending on the strength of GSM signals, Wi-Fi and Bluetooth). Turn off the GPS receiver and turn off auto-adjustment of screen brightness.

We put the phone into service mode. For my Lenovo, this is the combination ####1111#, dialed in the dialer; For Samsung phone The combination *#0228# is suitable. I think you can easily find this combination for your device on the Internet. By the way, I came across a combination like *777#, which many people complained about: having completed this USSD request, smartphone owners received from the operator cellular communications some wildly expensive set of unnecessary options. It was probably a scam on the website with service codes, I don’t know. In any case, turning on the “airplane” mode will protect you from this. Also, keep in mind that service codes for phones they usually start with *# (yes, there must be a hash) and don't require pressing the call button.

So, we entered service mode. Structure service menu unique for each device manufacturer. In my Lenovo, I selected Item Test → BatteryChargingActivity, in Samsung some parameters simply appeared, and I scrolled down a couple of times until the desired values ​​appeared.

To check the charges, we will control the current strength. It can be designated as Charging Current, measured in mA (milliamps) and has the value “zero” when charging is not connected.

We collect chargers that interest us. It would be better if there were more of them and they had removable cables, then the quality of the analysis would be better.

I took several chargers with a USB output and, accordingly, several USB → microUSB cables. By connecting them to various combinations to my device, for each combination I determined the minimum and maximum charging current (it floats a little in time) and wrote them down in the table.

Charge current in various combinations of chargers and cables in milliamps (minimum and maximum values)

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At the same time, let’s calculate how many percent the current floats during charging. Let's write the results in the second table.

Percentage change in current during charging

Based on the measurement results, the following conclusions can be drawn:

• The displayed current is not measured exactly, but in increments. Accordingly, you should not pay close attention to the exact values ​​of the measured current.
• My phone consumes about 1,000 mA when charging (this can be seen on cables No. 1 and 2 in combination with charges No. 1, 3 and 4 - the current values ​​​​are similar to each other and are the maximum of all measurements). This is evidenced by the maximum current written on the “native” charger - 1,000 mA.
• Cables No. 1 and 2 transmit charging voltage equally well.
• Cable No. 3 has high resistance, so the charge current is much less than expected. It can only be used for charging in hopeless situation. With GSM, Wi-Fi, and Bluetooth modules turned on, it is unlikely to even be able to maintain the battery level.
• Charging No. 2 (declared as one-amp) gives a negative current, that is, flowing in the other direction. Instead of charging, it discharges the gadget. By the way, the Samsung phone did not show a negative current, but only zero.
• Charge No. 4 - from the iPad, stated as giving 2,400 mA, has the most high power(this can be seen on the “high resistance” cable No. 3). Charging No. 3 (declared as three-amp) - dual, both connectors charge the phone equally well, but when connected to it more powerful load(for example, a tablet) will give more current through the second port. If we roughly estimate the ratio of the maximum currents on its connectors obtained on a bad cable (280 and 410 mA), the first connector is capable of delivering 1,200 mA, and the second - 1,800 mA. This is indirectly confirmed by the maximum current drawdown (in the second table): the more powerful the charging, the less the drawdown.
• Charger No. 5 (car charger, in the cigarette lighter) provides insufficient current for charging (compared to charges No. 1, 3 and 4). Indeed, when traveling south with a smartphone in navigator mode, during 16 hours of travel, she was only able to maintain the charge percentage at the same value.

To rehabilitate cable No. 3 a little, let’s say that when it is used for a less demanding load, it interferes less: when charging a Samsung phone, instead of the required 453 mA, it transmits 354 mA, which can already be tolerated.

This is what happened after testing my charges. Your results will be slightly different, but general meaning, I think you get the idea: we find the maximum current from all combinations, identify successful cables and chargers, and separately analyze combinations that give less current.

Happy measuring!

A car charger is a very primitive device, consisting of only a few elements and capable of performing only one function: recharging a smartphone from the cigarette lighter while the car engine is running. However, despite the simplicity of a car phone charger, the choice of this accessory must also be approached very responsibly. Motorist using charger low quality, risks being without means of communication at any moment - if a charging failure occurs during a long trip, this will become a real problem for the driver.

First of all, the motorist must decide what he needs: full car charger or USB adapter. An adapter is an adapter from a cigarette lighter to a USB cable.

The adapter has a significant drawback: it turns into a completely useless thing if the motorist forgot the USB cable at home. Therefore, when contacting a communication store, the driver is recommended to take a full-fledged charger - it costs only a little more in retail than a USB adapter.

When ordering from China, preference should be given, on the contrary, to a USB adapter. You can buy such a “trinket” for only 130 rubles.

Other criteria for choosing an ASU include the following:

Output current. There is enough current to charge smartphones. 1 A, but to recharge the tablets you will need 2 A– this was mentioned in the article on choosing network chargers. It is recommended to take the ASU, which issues 2 A – With the help of such an accessory, the motorist will be able to recharge both a smartphone and a tablet. Worry about the fact that the smartphone is dated 2 A If it burns out, it shouldn’t: modern gadgets are equipped with special charging controllers - devices that do not allow excess current to pass through.

Output voltage. There is such a rule: the voltage specified in the technical specifications of a car phone charger should not exceed the value indicated on the gadget’s battery by more than 5%. Otherwise, the ASU will overheat and very soon fail.

Wire length and type. Experts unanimously advise taking ASU from twisted wire. The likelihood that the twisted wire will break (which could lead to a fire) is extremely low. In addition, the twisted wire is adjustable in length - very useful property, considering how diverse the interiors of modern cars are.

Wire fastening. It is worth making sure that there is a corrugated sheath at the place where the wire comes out of the adapter. Here's what we mean:

The corrugated sheath prevents the wire from breaking at bend points. The fastening of the wire to the plug must also be protected by it.

Number of ports. This criterion is relevant if the motorist chooses a USB adapter. Optimal number of ports – 2 : one with output current in 2.1 A, the second - in 1 A. A wonderful and inexpensive car USB adapter with two ports from the company Remax sold on the marketplace GearBest:

Buy adapters from a large number ports are only advisable for those motorists who are heads of large families or simply large families. Otherwise, the driver will pointlessly overpay for the accessory, because some of the ports will be idle.

Design. The driver should pay attention to the fact that there is no metal ring around the central contact of the AZU.

Since the charging body is made of plastic, sooner or later the metal ring will definitely break off the thread and remain in the car’s cigarette lighter. A stuck part can short-circuit the contacts inside the cigarette lighter, which can lead to a fire. To be fair, it should be noted that AZUs with metal rings are now on sale very rarely, although previously a significant part of the chargers had just such a design.

A useful advantage from a design point of view is the presence of an LED, thanks to which the driver can be sure that the charger is working correctly. This option is sold at AliExpress for just over 100 rubles:

Otherwise, as far as design is concerned, the motorist should rely on his own opinion. For example, he may prefer a charger with an LED display informing about the state of charge and voltage of the car’s battery.

However, such an accessory will cost about three times more than a regular adapter.

What to buy: original or Chinese copy?

Buyers of expensive gadgets, as a rule, do not spare money on the best accessories - as long as they are new mobile device nothing was in danger. Such clients insist that they be provided with original chargers, cables and USB adapters, because they believe that universal chargers can cause damage to the device's battery. But are they right?

More likely no than yes. If an iPhone 7 buyer asks to sell him the original ASD, the consultant will probably offer an accessory from the company Belkin– but not Apple. By visiting the online store of the official retailer of Apple equipment in Russia Re: Store the buyer will find the company's ASU accessories in the catalog Deppa, MOMAX, Juicies– but again there is no charging made by Apple.

You won’t be able to find the original on the Apple company’s website either. In fact, this means that Apple does not produce its own RAMs. Belkin, of course, produces excellent accessories, but in relation to the iPhone this company is still a third-party manufacturer.

Company Samsung On the official website it sells only chargers that provide fast charging. Such an accessory costs more than 1.5 thousand rubles!

Other original AZUs Samsung does not produce.

The user should not limit himself to finding an original car charger for his gadget.– if he finds one, then its price will make his eyes pop out of his head. Among the universal AZUs (even if made in China) you can find a lot of safe and high-quality accessories that will turn out to be even more useful and effective than the originals. In the next section, we'll highlight a few worthwhile options.

Review of the best car chargers for phones

Here are the ASUs and USB adapters that motorists should pay attention to:

Anker Power Drive 2. Charger Power Drive 2 from Anker can boast, first of all, that it is equipped with a system Menas MultiProtect, protecting the accessory from overheating and overvoltage. The driver does not have to worry about a possible fire and touch the charger with his hand every minute.

The technology is also interesting IQ Power. Thanks to this AZU technology from Anker recognizes the device and provides exactly the current strength so that charging is as fast as possible, but does not harm the gadget’s battery. The accessory has a very laconic appearance, is easy to use and is equipped with a small LED, which provides additional convenience. ASU cost from Anker– about 600 rubles.

Aukey CC-T1. This option is recommended to be considered by motorists who own smartphones that support fast charging technology - for example, Samsung Galaxy S7 or YotaPhone 2. Aukey has 2 ports: one standard, the other Quick Charge .

Recharge using standard port both a smartphone and a tablet are acceptable - the output current is 2.4 A. The adapter comes with a proprietary USB cable with a Micro-USB plug. The cost of the entire set is about 1 thousand rubles.

1byone. Charger 1byone- a great option for those who need a lot of ports and who don’t want to pay a huge amount for it. The adapter has 3 USB ports, each of which provides an output current of 2.4 A.

ASU 1byone It is also notable for the fact that it is equipped with a special IC chip, thanks to which it is able to detect connected devices (like an accessory from Anker) and decide how much current to apply so that charging occurs as intensely as possible. iPhone 6 with the help 1byone it will be possible to charge from 0 to 100% in just 1.5 hours, and iPad Air 2 – in 4 hours. This adapter costs a little over 500 rubles.

Unnamed charger with LED screen. Chinese trading platforms GearBest And AliExpress They have already accustomed their regular customers to the fact that goods of very decent quality may not have a brand or name. This device is worth recommending to a motorist who is looking primarily for cheapness:

Charging with simple name Car Charger has two USB ports and delivers current up to 3.1 A for both. When using one port, the output current is approximately 2 A– therefore, you can successfully recharge tablets and phablets. The LED display shows the device's temperature and, in theory, allows the user to prevent overheating. However, for domestic motorists, information about temperature is useless - the Fahrenheit scale is used, which is not possible to change to the Celsius scale.

The cost of this “Chinese miracle” is just over 150 rubles.

Conclusion

A driver choosing a car charger for a gadget needs to pay attention to the price of the accessory and whether it is original, last of all. Specifications and visual inspection The AZUs will tell the motorist much more about the quality of the device than the manufacturer’s regalia.

You should not refuse to purchase a car adapter just because it was made by the Chinese. In our review of the best chargers, we mentioned products from the Middle Kingdom, but here are the “dinosaur” chargers of the mobile accessories market – an American company Belkin - ignored. Belkin puts a price tag of 1.5–2 thousand rubles on its exercises - although not according to technical specifications, neither in terms of build quality are the accessories of this company superior to their Chinese counterparts costing 200-300 rubles.

Now the most universal and reliable way to charge a smartphone is to use chargers with a USB port. People who drive a lot and don’t want to be left with a dead smartphone in the middle of the road are forced to buy car chargers for themselves. Among the hundreds, if not thousands of car chargers on the market, we can recommend ten of the best for purchase, which stand out for their design, build quality, number of ports and high power output.

10. R2D2 car charger fits cup holder ($40)

Fans of the fantastic Star Wars saga will love this car charger, made in the shape of the R2D2 robot. Unlike most competitors, the R2D2 car charger fits cup holder is placed in the cup holder and connected to the cigarette lighter with a separate cable.

9. Back To The Future Flux Capacitor car USB charger ($25)

This charger is a real find for geeks, made based on the series of science fiction films "Back to the Future". Upper part with beautiful LED lighting with a tricky interweaving of wires, it is just a beautiful decoration, even if you accelerate exactly to 141.592 km/h (88 mph), you will not be able to travel through time. There are two USB ports for 1 and 2.1 amperes.

8. Vano 4-port USB car charger ($15)

With this car charger you won't be short of USB ports; four of them should be enough for all occasions. Vano 4-port USB car charger is capable of delivering a total of 6.8 amperes, which is enough to simultaneously charge a smartphone and tablet.

7. Incipio USB & Lightning ($40)

The Incipio USB & Lightning car charger is made specifically for iPhone smartphones and tablets iPad computers. There is a non-removable Lightning cable and a standard USB port for other mobile devices.

6. Aukey CC-T1 2-Port USB Car Charger ($17)

This is one of the few chargers on the market that has two USB ports, one standard and the other supporting fast technology. charging Quick Charge 2.

5. Motorola TurboPower QuickCharge 2.0 ($30)

Motorola made this charger for their phones that support the technology fast charging QuickCharge 2. However, Motorola TurboPower QuickCharge 2.0 works great with other QuickCharge 2.0 smartphones.

4. Ventev Dashport q1200 ($20)

This charger supports Quick Charge 2.0 fast charging technology. If the smartphone also supports Qualcomm Quick Charge 2.0, then it will charge very quickly from the USB port.

3. Anker 48W 4-Port USB Car Charger ($15)

If you need a car charger with more than one USB port, then the Anker 48W 4-Port USB Car Charger with four USB ports is a great choice. The total power that the charger can handle through four ports is 48 watts. Plus Anker can dynamically change the current depending on how much “electricity” the smartphone consumes.

2. Xentris Quick Charge 2.0 Vehicle Charger ($35)

The main feature of this charger is its support for Quick Charge 2.0 fast charging technology. If your smartphone supports Qualcomm Quick Charge 2.0, it will simply charge at reactive speed. The cable included with the Xentris Quick Charge 2.0 Vehicle Charger has a built-in LED backlight, so that it is easier to connect it to the microUSB connector on your smartphone in the dark.

1. TYLT Ribbn ($40-50)

Despite the frivolous appearance(after all, bright, poisonous colors are usually chosen by young people), this is a very serious car charger, capable of outputting 2.4 amperes. The most interesting thing is that few conventional wall chargers are capable of delivering more than 2 amps. For convenience, TYLT Ribbn comes with a non-removable meter flat microUSB or Lightning cable, which cannot be lost. In addition, there is an additional standard USB port for connecting a second mobile device.

I have seen articles about the development/refinement/production of ready-made sources for cars, where the authors do not think about such things as safety circuits. In my source, the protection scheme turned out to be more complex than the source itself, because A fire in a car is certainly unpleasant. How did the subjects perform and why? only one survived- in this article.

Why do you need your own charger?

Someone will ask: “Why develop your own charger if there are plenty of ready-made devices?” Like many car enthusiasts, I use several additional devices in my car for which standard power is not provided. The current situation in the car power supply market is the use of the cigarette lighter socket for everything. As a result, there are wires all over the cabin, it is unclear whether the recorder is turned on or not... Probably, this is convenient for most users, but not for me. Suddenly I wanted to have USB sockets so that any device could be charged quickly, just like at home, so that nothing would stick out in the cigarette lighter and would not interfere with closing the curtain near the automatic transmission selector. I wanted the recorder to simply turn on and work while driving, and the rear passengers would not break its adapter with their feet. Fortunately, there was nothing ready-made - and now I’m already drawing a diagram!

​List of tested devices

1. Gerffins CC02
2. Samsung Car adapter
3. Phantom PH2163
4. Deppa Ultra duo
5. Ginzzu GA-4415UW
6. Stark CC2USBSTWH
7. GAL UC-1127M
8. Ginzzu GA-4015UB
9. Pockets SPECHR-011
10. Belkin RoadRockstar
11. My 4USB

Testing

When conducting tests, I tried to follow the recommendations of two standards:

1. ISO 16750-2, Road vehicles - Environmental conditions and testing for electrical and electronic equipment - Part 2: Electrical loads
2. ISO 7637-2, Road vehicles - Electrical disturbances from conduction and coupling - Part 2: Electrical transient conduction along supply lines only. Local equivalent - GOST 28751, Electrical equipment of automobiles. Electromagnetic compatibility. Conducted interference on power supply circuits. Requirements and test methods.

Unfortunately, the equipment did not allow us to do all the interesting tests - high-voltage and “fast” ones could not be done. However, all devices were prepared and the protection schemes were studied, which makes it possible to judge the resistance to these influences.

Testing was carried out using two switching schemes from the ISO 7637-2 standard:

1. Voltage transient emissions test
2. Transient immunity test

Description of testing

Voltage transient emissions test (ISO 7637-2:2004 4.3)

This test is designed to evaluate the device as a source of interference on the power supply. A stand assembled according to this scheme is shown in the first illustration.

1. Oscilloscope (Keysight MSO-X 3104T 1GHz)
2. Oscilloscope probe
3. Network equivalent (homemade, see below)
4. Device under test (interferer)
5. Power supply (Keysight DC power analyzer N6705B)
6. Grounding

Where A is the power supply contact, B is ground, C is capacitor, L is inductance, P is the device under test contact, R is resistor.

Their characteristics:

L = 5 µH (no core);
Resistance between P and A:< 5 mΩ;
C = 0.1 μF at 200 V a.c. and 1500 V d.c.;
R = 50 Ω.

The coil resistance turned out to be slightly higher than specified in the standard, so I can’t open a certification laboratory.

Oscillograms taken:

• at the moment the input power is turned on
• turn off the input power
• interference during operation at rated load

The full voltage swing was measured, rise-fall times were not measured. In normal mode, the frequency of the main interference was measured (often it was not alone).

CVC

The composition of the stand is the same as in the Voltage transient emissions test. The voltage at the device output at rated current and current consumption were measured. The load is simulated by the same N6705B device - it has 4 ports, each with its own internal module, some modules can be used as a load. The rated current was consumed from only one USB port, For multi-port devices, efficiency and maximum interference data may not be accurate. The resistance of the wires was removed to enter corrections.

Compatible with different devices

Charging capability was checked Apple iPad and Samsung Galaxy, the input current was measured.

Transient immunity test (ISO 7637-2:2004 4.4)

This connection circuit is intended for testing resistance to transition processes. All subsequent tests were carried out according to this scheme.

1. Oscilloscope (internal oscilloscope on Keysight N7973A)
2. Oscilloscope probe (not included in our configuration)
3. Test Pulse Generator (Keysight N7973A 60V 33A)
4. Device under test
5. Grounded surface(grey metal sheet)
6. Grounding
7. Optional resistor (not available in our configuration)
8. Optional diode bridge (not available in our configuration)

Pulse 2b (ISO 7637-2:2004 clause 5.6.2b)

Simulates interference from motors DC operating in generator mode after the ignition is turned off.

Impulse 4 (ISO 7637-2:2004 clause 5.6.4)

Simulates a power loss caused by turning on the starter of an internal combustion engine, excluding surges caused by the start.

Impulse 5b (ISO 7637-2:2004 clause 5.6.5)

This test simulates the Load Shedding disturbance that occurs when the battery is disconnected. The generator continues to supply charging current, while the remaining loads remain connected. Under a menacing impulse 5a Two devices were hit: No. 4 and No. 11. Both were burned. Then I read that modern cars have a suppressor, and such stresses will not occur. No. 4 dropped out of further testing. For all other devices, the following pulse (LV124) was used instead.

LV124/VW8000 2013-6:E-05 “Load dump”

The essence is the same as impulse 5b, but it is defined by the manufacturers Audi, BMW, Daimler, Porsche and VW. Taken from Keysight brochure.

Direct current (ISO 16750-2 clause 4.1)

This test verifies the operation of the equipment between the minimum and maximum supply voltage. Evaluation criterion: class A.

Overvoltage (ISO 16750-2 clause 4.2)

This test simulates a situation where the generator regulator has failed and its output voltage has exceeded normal values. This test simulates "lighting up". I supplied 24V voltage for 60s from clause 4.2.1.2. Evaluation criterion: class D.

Superimposed alternating voltage (ISO 16750-2 clause 4.3)

This test simulates the added alternating voltage on top of the permanent one. The frequency changed 50Hz - 10kHz - 50Hz, in the standard up to 20 kHz, in ours up to 10 kHz, the source could no longer do so. Evaluation criterion: class A.

Starting profile (ISO 16750-2 clause 4.5.3)

This test checks the behavior of the device under test during and after startup. Evaluation criterion: class C. Essentially, it is the same as Imuls 4 from ISO 7637-2, only the oscillation on the shelf has been added.

Short circuit protection (ISO 16750-2 clause 4.8)

This test simulates short circuit device inputs and outputs. We shorten all the contacts of one USB output among themselves, i.e. to the ground. The standard requires a short to ground and to the 12V power supply, but the second option is not possible for us, and I did not simulate it. Once it happened by accident - one of the Ginzzu “GA-4015UB” burned out. Evaluation criterion: class C.

Reversed voltage (ISO 16750-2 clause 4.6)

This test verifies the device's tolerance to reverse battery polarity when the jump starter is used. Apply -14V to the input for 60s. Evaluation criterion: after replacing blown fuses class C. No external fuse was used, one 10A standard FUSE was burned - at a current of 33A it took 150 ms, which is much more than any burned device could withstand.

Preparation

When the smell of burnt electronics subsided, I began to disassemble all these devices. I present everything in order with comments about the protection scheme, the scheme USB connections connector, general impressions.

What are they like inside?

The best of the devices purchased - self-recovering fuses at the input, a suppressor, an LC filter, diodes for protection against reverse voltage. The wiring is neat, the device is highly complicated, apparently to save on source microcircuits. There are options for connecting the D+ D- lines to voltage dividers for Apple, but they are shorted. It is written that it was developed in the USA, manufactured in China, the property of Euroset. They don’t want to develop with us...

Samsung Car adapter

LC filter, fuse, after replacing which (soldering) the device works. Accurate tracing.

Phantom PH2163

Input protection is not provided; the electrolyte has exploded. The power chip was sanded (copy protection?), the chip was pierced.

Deppa Ultra duo

A fuse, after replacing it (soldering) the device works. On one port D+ D- are connected, on the other - dividers. IC sanded. Accurate tracing.

Ginzzu GA-4415UW

No protection provided. On one port D+ D- are connected, on the other - dividers. The board was badly damaged. The tracing is bad - the location of the inductor and the microcircuit. But English-speaking users are offered 4.8A versus 3.1A for Russians. In milliamps the characteristics are the same!

Stark CC2USBSTWH

A fuse, after replacing it (soldering) the device works. On one port D+ D- are connected, on the other - dividers. The throttle is far from the chip. But a single-layer board...

GAL UC-1127M

The fuse has not tripped. Low quality board.

Ginzzu GA-4015UB

No protection provided. On one port D+ D- are connected, on the other - dividers. True, the user will have to figure out which one is which on his own. Dense layout, elements are filled with some kind of compound. Killed 2 pcs.

Pockets SPECHR-011

A fuse, after replacing it (soldering) the device works. There are options for connecting the D+ D- lines to voltage dividers, but the lines are shorted.

Belkin RoadRockstar

A fuse, after replacing it (soldering) the device works. Suppressor, fuse, LC filter on the plug side, fuse and filter on the passenger side. Remarkable quality of development. IC to identify the device as original charging by different consumers.

My 4USB

Fuse, suppressor, e-Fuse, IC to identify the device as original charging by different consumers.

Where Iout is the output current of the device; Vout - measured voltage at the consumer; Vout c - voltage at the device output, taking into account the drop on the wire; Iin - current consumption; Pout- output power; Pt is the power of heat losses in the device; n - efficiency; Vp-p on, off, noise - voltage swing when switching on, switching off and operating, respectively; F noise - interference frequency.

The test cells are marked with letter grades. Letters are functional status classes (ISO 16750-1 clause 6):

• Class A. All device functions operate normally during and after the test.
• Class B. All device functions operate normally during the test. However, one or more are outside the specified tolerance. After the test was completed, the device automatically returned to normal operation. Class A memory functions.
• Class C. One or more functions of the device did not work as expected during the test, after the end of the test the device automatically returned to normal operation.
• Class D. One or more device functions do not function as expected during the test, and after the test ends the device does not return to normal operation until the user restarts it.
• Class E. One or more functions of the device do not operate as expected during the test; after completion of the test, the device cannot be returned to normal operation without repair or replacement of the device/system.

Why is class C green and class B yellow?

We can turn a blind eye to the standard’s requirement to maintain full or partial functionality during the test, because for charging it is important not to burn out or set fire to the devices being charged. Class A and C I think better class B - either we do it as expected, or we don’t charge anything.

Analysis of results

To be honest, I expected much worse results, fires and smoke screens, I even set up a camera to record everything, but there were no beautiful fires.

According to the testing results, all chargers delivered the rated current; some devices are ready to deliver more than what is written. Only two chargers (Belkin and mine) limit the current according to USB ports, the rest have 5V ports in parallel, only the source is limited. Statements on packages about current at ports are of an advertising nature. Many manufacturers make it possible for Apple lovers to charge their devices, mainly using resistors.

Device efficiency from 82% to 90% is quite decent, but for small devices with high current long work not guaranteed. On a long trip, the Ginzzu will need to be cooled periodically.

Some charges produce strong interference into the network (up to 7.2 V), which can negatively affect the quality of audio and radio reception.

Only one of the purchased devices (Gerffins) turned out to be resistant to negative voltage. Moreover, some of the fire victims supplied a negative voltage to the USB before their death (measured only down to -3 V, because the power supply protection was triggered). Someone will notice that when reversing the polarity of the batteries in the car, much more valuable things will burn out (only the fuses should burn out), and this happens extremely rarely among extremely crooked people. But. The standard also includes pulses No. 1 (-150 V, duration 2 ms, group of pulses), No. 3 (-220 V, duration 15 ns, group of pulses), which occur without reversing the battery polarity.

Why don't developers install a diode?

I think three problems come together here: efficiency, lack of space and cost. In addition, many microcircuits allow you to work with increased voltage(34063A has a maximum input voltage of 40V), and the input capacitor can smooth out some of the noise. The efficiency with a diode will be worse (let's say - 10%), which for chargers that fit into the cigarette lighter socket is fraught with overheating (from the 3-amp Ginzzu I expected that it would overheat and burn out under the rated current, after an hour it began to reset, having become very hot, but didn't burn). For multiport chargers, the diode will dissipate a lot - for Belkin, with an output power of 36W, the total thermal loss will be about 10W, and now only 4W. If you install transistor protection, it will be expensive.

What to do

If we're talking about circuitry, install a diode, a filter, a fuse, a suppressor. Instead of a diode I installed electronic key from TI LM5060

Conclusion

Not all car chargers are equally useful. Some may even cause fire (although maybe it was Honda's fault).

Devices sold for use in harsh conditions are not subject to mandatory certification in the Russian Federation. Among the purchased devices, only one passes the tests; all the others burned out.

P.S. Thanks to Keysight for the loaner equipment and clarification. Good analyzers and an oscilloscope, I hope the software will be improved later. I was very pleased with the opportunity to synchronize and manage all this equipment from one workstation via the network. Thanks to @dimonfofr for building the network equivalent and helping with testing.

P.P.S. Pay attention to the instructions for the memory - there is a lot of fun there. Pockets recommends turning it off mobile phone before charging, Stark - turn off charging while starting the engine, Deppa can sync your device with your computer, Phantom recommends keeping the cigarette lighter socket clean.