Wednesday, September 26, 2012

Now we’re chargin’ with gas: ASUS Ai Charger

After finishing yesterday’s post on iPhone charging from a USB 3.0 port, I came across some references to ASUS Ai Charger. It’s a Windows software tool produced by motherboard manufacturer ASUS. It claims to increase the charging speed of iThings connected to the computer, and it works with non-ASUS motherboards, and apparently even laptops.

Few details are provided, and it sounds kind of sketchy, but I gave it a try on my EVGA X58 SLI LE motherboard. After installing and rebooting, there’s a new icon in the notification area:


Clicking, double-clicking, or right-clicking on it has no effect. When I plug my iPhone into a motherboard USB 2.0 port, it changes:


Plugging it into a port on my USB 3.0 add-on card has no effect.

So, what’s the verdict?

image(Click to embiggen.)

It works! The purple charging curve, with Ai Charger, is almost identical to the green 1 A wall charger curve. (It’s offset slightly, because Ai Charger’s magic doesn’t kick in until the iPhone turns on and identifies itself to the computer. If I weren’t starting from a dead battery, there would be no delay.)

I don’t really know how Ai Charger works—it seems to look for a device that it recognizes as an iThing, and then tells the motherboard chipset to do something. There are some reports of blue screens on the Internet, and it’s not clear what motherboards or chipsets it supports. But if you’d like to charge your iThing faster, it seems to be worth a try.

Tuesday, September 25, 2012

iPhone 5 does not charge faster over USB 3.0

For a followup, with a solution for faster charging on many Windows PCs, please see: Now we’re chargin’ with gas: ASUS Ai Charger.

USB 2.0 ports are, according to the specification, limited to providing 500 mA of current to connected devices. The Apple iPhone charge provides 1000 mA, so it can charge an iPhone about twice as fast as a standard USB 2.0 port.

USB 3.0 increases the current limit to 900 mA. Even though the new Lightning-to-USB cable is a USB 2.0 cable, I was hoping that it would take advantage of the higher current limit when connected to a USB 3.0 port. After all, there are USB 2.0 ports on Apple computers and some PC motherboards that are capable of providing higher currents to iPhones and iPads.

Unfortunately, this is not the case:

imageClick to embiggen.

The charging rate when connected to a USB 3.0 port is basically identical to USB 2.0, and much lower than the wall charger.

These tests were conducted on my iPhone 5 within a few days of release day. My procedure was to deplete the battery, using the Drain My Battery app, until the phone shut off. After a couple of minutes to cool off, I connected the phone to a power source, and treated that time as a 0% charge. When iOS was back up and running, I used the Battery Magic app to monitor the charge percentage. I recorded the time and charge percentage manually at irregular intervals of a few minutes, until the app reported 100% charge.

The wall charger is the small, cubical 1 A charger included with the iPhone 5. The USB 2.0 port was a back-panel motherboard port on my EVGA X58 SLI LE motherboard. The USB 3.0 port was a back-panel port on a Syba SD-PEX20122 PCI-Express card in the same system. The USB 3.0 card is properly connected to a molex power cable. Neither of the USB ports claims to have any special, high-current or iThing-specific modes, just the normal 500 mA and 900 mA limits appropriate to their versions of USB.

Sound quality issues with iPhone and Blackberry Remote Stereo Bluetooth Gateway

The Blackberry Remote Stereo Bluetooth Gateway is a Bluetooth music receiver that I use in my car to play music from my iPhone. It works great, but it’s no longer in production, so units that are still for sale are generally expensive. This is a troubleshooting tip for owners.

Problem: Sound is garbled, distorted, crackly, or muddled.

Solution: The Gateway doesn’t sound good when the iPhone volume setting is at its maximum. While playing through the Gateway, reduce the volume setting by about 2 clicks of the volume-down button.