Handtops, UMPC - Proprietary power supply?

10/11/04 + vadsoom

Greetings,

Do any of you with hands-on OQO experience have any knowledge about the power supply? Will the OQO require it's own or will an off-the-shelf replacment function?

Like some PDAs, is it possible to charge the OQO through it's USB port?

Thanks in advance!

Recent Blog: I finally did it.., went on a business trip with only my OQO

10/20/04 + DoC

The pinouts and connector on the battery match the standard level2 LiPoly smart-battery. That means they've probably got a MAX1667 chip (charge controller) in the power supply. Maxim holds the patents on all forms of lithium charging technology so there's probably no alternative to OQO having used that specific charge controller. It's a 20 pin SSOP package. It should be easy enough to build a circuit around that to take DC power as an input for car and plane use.

Considering that, I'm getting ready to order 10 2200mah LiPoly batteries and see if I can cram them into a package the size of the OQO along with that max-ic. Now all I need is to find compatible sockets and plugs and I'll have a powerbrick that can keep the OQO going for 9-24 hours solid depending on application requirements. Unfortunately full charge time on the pack will be about 6 hours instead of the 1 hour we should see with the OQO. With two of the max-ics built in, it should be able to charge itself as well as charging the OQO's internal battery.

10/20/04 + pat

Would it be feasable for a firm like Mobility Electronics (manufacturer of IGO Juice 70) to make a tip for the OQO?

10/21/04 + vadsoom

I'm still worried about the inverter issue. Since I would using the OQO for travel (GPS and MP3), not being able to use it in a vehicle would be a killer for me. Anyone heard back from OQO on the inverter issue?

Thanks Much!

Recent Blog: OQO model 02 hands on mini-review

10/21/04 + garylm

As long as the inverter puts out a nice 60Hz (or 50Hz) sine wave, the OQO's power supply won't know the difference.

I suppose some inverters may exhibit flakey behavior, depending on whether they're driving an inductive or resistive load. We might need to look into what kind of load the OQO's power supply presents to the line.

Recent Blog: Travelling With the OQO

10/21/04 + DoC

Running a DC device with an AC adapter on an invertor is rather silly anyway. Hopefully we'll have a commercial DC-DC power supply for the OQO in the near future. The thing runs on 4.2v at less than 3amps so it should be relatively easy to power. The trick is just getting the charge controller in there. You should be able to do a relatively cheap DC-DC power supply with the charge controller built. Amazingly, that same maxim charge controller acts as a switching power supply. You feed it up to 29 volts DC and it outputs the voltage and amperage that the battery asks for. So all you need is that chip and a small assortment of caps and resistors and a small inductor and you are in business.

I'd be suprised if IGO came out with a tip for it but it wouldn't be impossible. The tip would just be a little more bulky than normal to support the charge controller.

It probably wouldn't hurt anything to just hook up the two power pins on the connector and give them < 4.2v. I'd keep it at 3.7 maximum if you leave the battery in. To be perfectly safe you should take the battery out, though.

10/22/04 + vadsoom

DoC,

You're probably right. A nifty fitted case, a cheap regulator and there isn't any reason why the OQO couldn't run off non-proprietary batteries. Hmmmmm - got me thinking....

I'd love to see a AA battery pack that would fit the OQO! NiMh AAs are topping out now at 2200mA and continue to improve. It's only a matter of time before new technology in standard batteries catches up. It would be great to power the OQO from standard batteries in a pinch. Sure, you wouldn't get 2-3 hours of battery life and the battery would certainly be larger, but at least you wouldn't have a dead uPC on thise occasions where you need it most.

I once made a battery pack for my Libretto that kept it kicking for almost an entire flight from Chicago to Tokyo. When I arrived, I just tossed the spent "D" batteries. To be able to do the same for the OQO would be wonderful.

In my international travels, I've found that AAs are available in even the smallest, most rural places and were more accessable than power sockets. ;D

Recent Blog: OQO model 02 hands on mini-review

10/25/04 + volker

Now for all about possible "car adaptors" the latest info from OQO (24th Oct.):

"At the moment we can't recommend any car adaptor that will work with the OQO."

10/27/04 + DoC

Everyone PLEASE go to iGo and do the following:

We currently do not have a tip for the product you requested. Tips are designed according to the market demand.

If you would like to request consideration for a particular product please go to link. On the left hand side is the "Solution Finder". Under "Type of Product" scroll down to "Can't Find a Product". Please fill out the make and model of the product you are looking for.

This information helps influence the decision-making process. It goes directly to our Marketing and Compatibility Departments.

The more of us who submit requests, the more likely iGo will come out with tips for the OQO.

10/27/04 + tke918

done! ;)

edited: Nov 11 2004 + garylm

A pure sine wave inverter for your car

Looks like the two outlets are too close together for wall warts though.

Recent Blog: Travelling With the OQO

11/12/04 + Chekote

Thx Gary

. Thats a lot cheaper than I was expecting too.

Recent Blog: Flipstart Camera

11/12/04 + DoC

Not bad.. It's a serious waste of power, though. Invertors lose a hell of a lot in heat. And I certainly wouldn't want to carry that on an airplane with me.

edited: Nov 20 2004 + DoC

Interestingly enough the OQO power supply outputs 5.28v even though it's rated as 4.8. It drops to 4.95 while plugged in and battery charging. Sounds like a 5v supply might do it as long as you can come up with a connector which shouldn't be that difficult. It may drop further (under control from the PC via the i2c bus) when the battery is charged, I'll let you know in a bit. If it drops to 4.2-4.5 when charging is done then it may need to be a little smarter than than a simple connector.

11/20/04 + DoC

It looks at first glance like the charge controller is internal and they just use the i2c bus to the power supply to know when it's connected rather than having a switch or voltage detector in the connector and circuitry to tell the OS that it's connected via i2c. That means it might do nothing more than allow the OS to change power profiles when it's connected although there is still a possibility the power supply actually reduces it's output when it's told the battery is done charging. I'm waiting for my unit to get back to full charge to see.

edited: Nov 20 2004 + DoC

OK! Great.. the battery is done charging and the voltage reading is now 4.99 which means the OS doesn't tell the power supply to reduce output when the battery is charged. This means you can safely use a 5v supply without any additional circuitry!!! However, without the additional circuitry the OS won't switch to powered mode so any power-saving features enabled for battery-only operation will take effect. This is fine for external battery use but probably not if you want to replace the power supply entirely.

This is good news since it means I can use socket's Mobile Power Pack or other 5v packs so long as we can come up with a very simple adapter.

It should also mean a simple voltage regulator that takes 12v input and 5v output would be sufficient for car and air charging.

Obviously, using unapproved connectors and power supplies will void your warranty.

As soon as I get my sacrificial power supply (my accessories orders haven't arrived yet) I'll post some details on the amp draw in various states. I need an in-line connection to do that and I don't want to cut open my one and only power supply at the moment. ;P

Posative is on the right, negative on the left when looking at the socket on the OQO.