04-28-2012 08:53 AM - edited 04-28-2012 09:04 AM
Fast charger, besides being more versatile, has the potential to charge around twice as fast as the dock with the TPT on. Same rate when TPT is off. Lenovo handicaps both the dock and wall charger to less than half their capacity when the TPT is powered. This came to light in this thread;
Here are two graphs (charge/time and current/time) for the fast charger while TPT is in standby. Battery was charged from 8% charge to 100% charge, took 105 minutes (0 to 52 minutes is not to scale). Similar would apply to the dock with TPT off;
05-01-2012 02:44 PM
Okay now seriously... this is kinda getting ob my nerves. Now I'm really thinking about creating my own charger.
I have a versatile professional balance charger, the kind of chargers people use for model airplanes for example. I could create a cable to connect the tablet to that charger. I would just need to know what kind of battery there is inside this tablet. Lithium Polymer? Lithium Ion? How many cells? And what's the capacity? If someone has these infos, please tell me!
05-01-2012 05:23 PM
05-02-2012 02:21 AM - edited 05-02-2012 02:22 AM
Yeah... There are good engineers and there are bad engineers. Some want to deliver a perfect, beautiful solution and some just want it to work and then go home at 5 o'clock... More importantly however, there are finance departments, that force engineers to work quicker. There are other factors as well. So, like usual, it's not just black and white...
Edit: By the way: Think positive. If we're lucky all of this stuff is adressed in the Android 4 update later this month =)
Enough off-topic now.
So, once again, I'm thinking about building my own charger cable and using my professional charger. With this one, you can specify the amps, the volts and the charge thats going in there. However, after reading about the differences in USB charging and charging with the Dock, which uses the dock connector, I'm wondering wether I should just buy a micro USB pin or start my research on getting the dock pin and using this one.
05-02-2012 05:25 AM
So, once again, I'm thinking about building my own charger cable and using my professional charger. With this one, you can specify the amps, the volts and the charge thats going in there.
What your charger can do is somewhat irrelevant in terms of optimal performance. The TPT firmware is going to limit current via the dock connector to 1A maximum (load plus charging current) and if you exceed 20V at the dock connector you probably risk damaging the buck converter (or whatever is used to step down from 20V) in the TPT. IMO, the most you'll probably achieve is a less aggressive charging profile than what I indicated.
Forget charging via the micro-USB connector, that's a dead end based on the connector itself. All you need is 20V at the dock connector (it uses two pins for the positive) controlled by what seems to be an internal interlock (probably to prevent charging if the battery is removed or defective). Fancy voltage/current source is a waste of time and money.
06-08-2012 10:11 PM