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Mini USB Micro USB Converter

Hey guys!

I was sitting at work with my 8 day old D2G. Im all thered up to my laptop and started noticing that when i use my tether i am consuming power faster than i can charge it. =] being the nerd i am i know that this isn't ridiculous.

My question is this:
If I use a usb cable meant for external hard drive (the ones that sometimes require you to plug into two USB ports) will I be able to charge the phone faster? Of course I will also be using the mini to micro converter but I do not see that causing any problems.

Is there a risk if i do this? I'm pretty sure even if I use two USB ports to charge it still won't charge the battery as fast as the rapid charger the phone comes with.

Thought, ideas, and criticism is greatly appreciated =]

for reference:
Amazon.com: 6FT External HDD USB Y Cable: Electronics
+
Amazon.com: OEM Mini USB to Micro USB Adapter (SKN6252) for Verizon Motorola Adventure V750: Electronics
 
Both the Droid 1 & 2 (along with the Global, R2D2, and X) use the same AC adapter which is rated at 850 mA (850 milliamps) of current. However, the USB Standard output for power in a unit load is defined as 100 mA for low power devices such as thumb drives in USB 2.0, and was raised to 150 mA in USB 3.0. A maximum of 5 unit loads or 500 mA for high powered devices such as hard drives can be drawn from a single port in USB 2.0, which was raised to 6 unit loads or 900 mA for high powered devices in USB 3.0.

As you are aware, some devices like high-speed external disk drives may require more than 500 mA of current and therefore cannot be powered from one USB 2.0 port. Such devices usually come with a Y-shaped cable (as you mentioned) that has two USB connectors to be inserted into 2 powered USB 2.0 ports on a computer or powered USB 2.0 hub. With such a cable a device can draw power from two USB ports simultaneously. Theoretically, this would provide up to 1 A (Amp) or 1,000 mA of power from a USB 2.0 powered hub or USB 2.0 powered internal interface.

Since the phone is supplied with 850 mA from the home charger, which is a "standard" charger, and yet USB 2.0 only supplies 500 mA, it would make sense that the phone might actually discharge ever so slightly while using tether, especially since tether uses the phone's Cellular radio constantly. On the other hand, since the "rapid" chargers supplied with the car docking station (model SPN5400) provides (I believe) 950 mA, it appears that you could use the y cable with USB 2.0 as you suggested which would supply higher current comparable to the rapid charger (1,000 mA - 50 mA higher than the rapid charger), meaning it WOULD charge the phone like the rapid charger if you weren't tethering at the same time.

If you could install (or had) a USB 3.0 interface in the pc it would give you 900 mA from one port (50 mA shy of the rapid charging rate and 50 mA over the standard rate) with just the standard Motorola Droid1/2/Global/R2D2/X USB/Charging cable. Note, you would get as much as 1.8 A from a 3.0 powered hub or powered internal interface if you used the Y adapter on a USB 3.0 interface or USB 3.0 powered hub, but I wouldn't take that risk as it may be far too much for the battery and cause overheating or permanent damage. I suggest before you use the Y adapter, make sure it's not on a 3.0 interface or 3.0 powered hub.

By the way, this (Universal Mini to Micro USB Charger Adapter Converter - eBay (item 280531589175 end time Jan-03-11 19:51:59 PST)) is even cheaper (shipping included for $ 0.99) and would work just as well as the one you listed. I just bought 3 of them for less than $3.00 total shipped! Also, this (http://cgi.ebay.com/USB-2-0-Mini-5-...444?pt=LH_DefaultDomain_0&hash=item3a60627d0c) is only $1.78 shipped and is again a perfect replacement for the one you listed. Of course, you could go with this (http://cgi.ebay.com/STARTECH-USB2HA...354?pt=LH_DefaultDomain_0&hash=item45f730e5e2) but the cost of $21.66 is outrageous.
 
thanks for all the info. it reconfirms the theory i had in my head. X_X i actually cannot recall all the voltages and technical data off the top of my head but I figured it as such. as for USB 3.0 im no so sure that that tech is going to catch on.

all i really need to purchase is the converter seeing as i have a million and a half of the y cables. ill prolly do somthing to the tune of a benchmark. i should be able to collect suffient data since i am going back to shcool again and will be usong my phone quite often in different situations.

what do you think... charge time relative to battery life should be more than enough to prove or disprove the above mentioned. i don't think it is necessary or practical for me to actually whip out a voltage meter to know EXACTLY how much power is going in and out.

anyways thanks for reply. if anyone else has anything to chime in it could only help. i think this one was real a quickie

10:41PM *just bought 5 of these =]
 
what do you think... charge time relative to battery life should be more than enough to prove or disprove the above mentioned. i don't think it is necessary or practical for me to actually whip out a voltage meter to know EXACTLY how much power is going in and out.

Actually, the 950 mA "Rapid charger" is supposed to charge a dead battery to 90% in between 2 and 3 hours depending on the ambient temperature and resulting battery temperature (warmer batteries charge quicker). So given that information, the battery should actually charge slightly while tethering if using the "rapid charge" rate of 1,000 mA from a USB 2.0 Y adapter.:)
 
thanks for all the info. it reconfirms the theory i had in my head. X_X i actually cannot recall all the voltages and technical data off the top of my head but I figured it as such. as for USB 3.0 im no so sure that that tech is going to catch on.

all i really need to purchase is the converter seeing as i have a million and a half of the y cables. ill prolly do somthing to the tune of a benchmark. i should be able to collect suffient data since i am going back to shcool again and will be usong my phone quite often in different situations.

what do you think... charge time relative to battery life should be more than enough to prove or disprove the above mentioned. i don't think it is necessary or practical for me to actually whip out a voltage meter to know EXACTLY how much power is going in and out.

anyways thanks for reply. if anyone else has anything to chime in it could only help. i think this one was real a quickie

10:41PM *just bought 5 of these =]
Hi. I bought the Startech USB y-cable from Amazon a week ago. Today got around to testing it and it DOES NOT work with my Droid X. The idea of simultaneously rapid charging and syncing is good. I hope it works for your phone!:unsure:
 
so the y cable did absolutely nothing as in it didnt charge....or try to install drivers or anything?

im just waitin for the adapters to come in and then ill post up with results
 
so the y cable did absolutely nothing as in it didnt charge....or try to install drivers or anything?

im just waitin for the adapters to come in and then ill post up with results
Cables don't generally try to install drivers xD... The phone would sync with the computer but it wouldn't charge.:icon_evil:
 
so the y cable did absolutely nothing as in it didnt charge....or try to install drivers or anything?

im just waitin for the adapters to come in and then ill post up with results
Cables don't generally try to install drivers xD... The phone would sync with the computer but it wouldn't charge.:icon_evil:

Very strange... ALL USB cables are supposed to carry power and data (see below). Even a single cable (rather than Y cable) should at least trigger the recognition within the phone that it is connected to external power when plugged into a powered USB port, even if it isn't enough to actually charge (i.e. add to power).


Pin Name Cable color Description
1 VCC Red +5 VDC
2 D- White Data -
3 D+ Green Data +
4 GND Black Ground


Now, a non-powered USB port does carry some power, but very little.

USB power usage:
Bus-powered hubs: Draw Max 100 mA at power up and 500 mA normally.
Self-powered hubs: Draw Max 100 mA, must supply 500 mA to each port.
Low power, bus-powered functions: Draw Max 100 mA.
High power, bus-powered functions: Self-powered hubs: Draw Max 100 mA, must supply 500 mA to each port.
Self-powered functions: Draw Max 100 mA.
Suspended device: Max 0.5 mA

The OEM Power Adapter from Motorola supplies 850mA which is more than a powered hub port, but it is also designed to charge the phone to about 90% within 2-3 hours. A powered hub port with 500mA should accomplish the same level of charge in about 6 hours in a phone that is on (since while charging the phone is also using power), and within about 4 hours if the phone is in charge-only mode.

When you say it didn't charge, did it at least show the phone as being connected to an external power source?
 
so the y cable did absolutely nothing as in it didnt charge....or try to install drivers or anything?

im just waitin for the adapters to come in and then ill post up with results
Cables don't generally try to install drivers xD... The phone would sync with the computer but it wouldn't charge.:icon_evil:

Very strange... ALL USB cables are supposed to carry power and data (see below). Even a single cable (rather than Y cable) should at least trigger the recognition within the phone that it is connected to external power when plugged into a powered USB port, even if it isn't enough to actually charge (i.e. add to power).


Pin Name Cable color Description
1 VCC Red +5 VDC
2 D- White Data -
3 D+ Green Data +
4 GND Black Ground


Now, a non-powered USB port does carry some power, but very little.

USB power usage:
Bus-powered hubs: Draw Max 100 mA at power up and 500 mA normally.
Self-powered hubs: Draw Max 100 mA, must supply 500 mA to each port.
Low power, bus-powered functions: Draw Max 100 mA.
High power, bus-powered functions: Self-powered hubs: Draw Max 100 mA, must supply 500 mA to each port.
Self-powered functions: Draw Max 100 mA.
Suspended device: Max 0.5 mA

The OEM Power Adapter from Motorola supplies 850mA which is more than a powered hub port, but it is also designed to charge the phone to about 90% within 2-3 hours. A powered hub port with 500mA should accomplish the same level of charge in about 6 hours in a phone that is on (since while charging the phone is also using power), and within about 4 hours if the phone is in charge-only mode.

When you say it didn't charge, did it at least show the phone as being connected to an external power source?
It would say that it was charging but charge gauge would drop instead of rise. In other words, it would drop all the way down to about 10% and then cut off despite saying that it was charging...
 
When you say it didn't charge, did it at least show the phone as being connected to an external power source?
It would say that it was charging but charge gauge would drop instead of rise. In other words, it would drop all the way down to about 10% and then cut off despite saying that it was charging...

Ok, so that confirms my suspicions. Now there are a few possible answers to this problem. Some USB ports on PCs are individually "powered", while others are part of an on-board USB "hub" running off one port's power. For example, the rear ports are likely either all individually powered at 500mA or could be paired with each pair sharing the 500mA (i.e. USB 1&2 - 500mA, USB 3&4 - 500mA, etc.), whereas the front port may be piggybacked off of one of the back ports. If it happens that the front port is sharing a "hub" configuration with another port on the rear and that rear port is already being asked for maximum power by a device such as a WIFI USB adapter, what will happen is the two ports (front and rear) will "share" the maximum 500mA between the two (i.e. 250mA front, 250mA rear), and if it is sharing with more than one device, the power will be further divided between those devices like mine (front shares with USB 1&2 - total combined power 500mA between 3 potential separate devices). Even further still, the front port may actually be individually powered but may be a "low power" port supplying only 100mA, while the rears would probably supply 500mA each or in pairs.

This can be somewhat confusing since USB can effectively support 128 devices from one port through the use of hubs and daisy-chaining, and can even go as many as 5 devices deep in the tree by daisy-chaining (such as mine...computer to HP Parallel Wireless Printer Server, to external 1TB Western Digital USB drive, to SONOS music server, to external Buffalo 500MB USB drive, to another external Buffalo 1TB USB drive). If these devices all have their own power supplies as mine do, then none of them need the USB port to supply power and so they will all work as they do in my case.

I have ports that are built into the motherboard and are on the rear plate where the keyboard, mouse, & monitor plug in. Then I have one on the front that comes off of a set of pins on the motherboard. This front one shares its power with USB 1 & 2 on the rear, so that front one shares its power with TWO ports on the rear. For this very reason I also have a Firewire/USB peripheral card which has 3 individually powered USB ports and 2 Fireware ports. This occupies a PCI card slot on the rear by itself. I have a USB extension cable running from one of those ports on the card to a desktop jack that came with my laptop's Linksys Wireless USB adapter. I use that desktop jack for things such as a USB card reader, external drives, and for my phone. This jack not only powers the phone while on, but also charges the battery, albeit slowly but it does charge, which says to me it's supplying 500mA.

In your case, if the two USB jacks you are plugging the "Y" adapter into are sharing the same USB hub, then they aren't actually supplying two separate sources of 500mA, but are actually sharing the same 500mA so there would be no difference than simply plugging one in.:icon_eek: If you can find two distinctly different ports (even if one is on the front and one is on the back), you may find the cable works as expected. An other option is to buy a "powered" USB hub, which comes with a wall-wart (power adapter), and plug it into one of the ports on the computer. Then plug the two ends of the "Y" into the hub. Since the hub will supply 500mA to each port on itself, you will get the combined power of two ports, or 1,000mA.:icon_ banana:
 
It would say that it was charging but charge gauge would drop instead of rise. In other words, it would drop all the way down to about 10% and then cut off despite saying that it was charging...

Ok, so that confirms my suspicions. Now there is one possible answer to this problem. Some USB ports on PCs are individually "powered", while others are part of an on-board USB "hub" running off one port's power. For example, the rear ports are likely all individually powered at 500mA, whereas the front port may be piggybacked off of one of the back ports. If it happens that the front port is sharing a "hub" configuration with another port on the rear and that rear port is already being asked for maximum power by a device such as a WIFI USB adapter, what will happen is the two ports (front and rear) will "share" the maximum 500mA between the two (i.e. 250mA front, 250mA rear), and if it is sharing with more than one device, the power will be further divided between those devices.

I have ports that are built into the motherboard and are on the rear plate where the keyboard, mouse, & monitor plug in. Then I have one on the front that comes off of a set of pins on the motherboard. This front one shares its power with USB 1 & 2 on the rear. I also have a Firewire/USB peripheral card which has 3 powered USB ports and 2 Fireware ports. This occupies a PCI card slot on the rear by itself.

I have a USB extension cable running from one of those ports on the card to a desktop jack that came with my laptop's Linksys Wireless USB adapter. I use that desktop jack for things such as a USB card reader, external drives, and for my phone. This jack not only powers the phone while on, but also charges the battery, albeit slowly but it does charge, which says to me it's supplying 500mA.

In your case, if the two USB jacks you are plugging the "Y" adapter into are sharing the same USB hub, then they aren't actually supplying two separate sources of 500mA, but are actually sharing the same 500mA so there would be no difference than simply plugging one in.:icon_eek: If you can find two distinctly different ports (even if one is on the front and one is on the back), you may find the cable works as expected. An other option is to buy a "powered" USB hub, which comes with a wall-wart (power adapter), and plug it into one of the ports on the computer. Then plug the two ends of the "Y" into the hub. Since the hub will supply 500mA to each port on itself, you will get the combined power of two ports, or 1,000mA.:icon_ banana:
The rear ports are individually powered and the front ports connect directly to the motherboard header which individually powers both of them.

Just got a different cable to see if the first cable was designed incorrectly. The battery doesn't increase its charge despite the status indicator.

Beginning to think that there's a software limit on the phone that makes it not draw more than 500mA if it detects it being connected for data (any computer connection). Portable HDDs, which both these cables are for, don't have such limits. Unfortunately, if the computer the hdd connects to isn't designed to limit the current to each usb port to 500mA, then the hardware would be fried.

My conclusion is that Motorola (even HTC see above) didn't want to risk people frying their motherboards. If they factored in the y-cable, they'd have to remove the limit and hope that people's hardware would limit itself. I've also tested both these cables on my laptop and have the same results. I give up! Can't wait for mrmattch3w's results.:biggrin: LOL

-Edit-
BTW the above link shows how to mod a usb cable so that it can draw 1000mA from a single port. Not sure if it's safe but if mrmattch3w isn't looking to be able to simultaneously sync and charge then that's his solution. And thanks FoxKat for trying to help me.
 
Interesting...

Well, I can see phone manufacturers trying to prevent damage to computers due to excessive draw, but as I understood it, the port will only put out what it can, and the device can't make it "try" to draw more than the port is rated for. Considering this, I don't know why they would fear this happening.

I will have to experiment as well once I get the adapters I ordered. I do know this...my phone does charge from the desktop port I mentioned, and also at work from my desktop PC through an identical arrangement, so it is at least pulling 500mA. I'll have to put it through some heavy power-drawing operations and see if I can "get the power meter to turn backwards".

BTW, the hack for the cable explained does away with the data connection and uses those wires to carry additional current, so the cable then only works to power and charge. This is obviously not what you are trying to do, so it wouldn't work for you (or for most others).
 
wow. thjis thread is semi-poppin lol i took it off auto notify on my phone. interesting stuff going on hope to get more info. From the knowledge that I know, i know that each USB port is capeable to supply 5V...and some external HDDs need 10V to function. For a afact, i know that most of the newer iMacs have USB ports that put out 10V

i dunno exactly how many maH that is but i know it puts out potentially DOUBLE the amount of power. i think its moving more towards knowing what USB ports put out more power and how much power they put out.

@FoxKat...i believe if you set the USB setting to charge only that the phonge charges just like a wall charger
 
wow. thjis thread is semi-poppin lol i took it off auto notify on my phone. interesting stuff going on hope to get more info. From the knowledge that I know, i know that each USB port is capeable to supply 5V...and some external HDDs need 10V to function. For a afact, i know that most of the newer iMacs have USB ports that put out 10V

i dunno exactly how many maH that is but i know it puts out potentially DOUBLE the amount of power. i think its moving more towards knowing what USB ports put out more power and how much power they put out.

@FoxKat...i believe if you set the USB setting to charge only that the phonge charges just like a wall charger

I think you have volts and amps (milliamps) mixed up. The ports all put out 5 volts, but some devices need more milliamps than the ports are rated for. Each port can put out a maximum of 500mA, so to get to the up to 1A (1,000 mA) required by some devices, you tap two USB ports with a "Y" cable. Since USB is a standard, any devices that operate on the USB standard either use the 5 volts that the USB port supplies, or if they need more than 5 volts, they come with an adapter to supply the needed higher voltages from a wall outlet. The same holds true for external drives for instance, when they require more than 500mA, like one I have that has its own power supply. That drive only uses the USB port for the data and takes its power from the wall adapter instead.
 
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