Asus Eee-pc 1000H netbook. Running off a cigarette lighter..? - Page 1
Forum section: electronics / projects

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: November 20, 2011, 10:47:59 am
content: Hi. I have a Asus Eee-pc 1000H netbook. I searched around the internets for advice on charging this computer in the car. The simplest solution is a inverter and then connect the AC charger supplied with the computer. Another solution is to purchase an after-market purpose made 12V charger. Not knowing what circuitry they contain and the absent specs, it's all quite unsettling.The AC charger I have says output 12v 3A. But I'd like to know what the voltage limits are for the input of the laptop. I am concerned that if the car's engine is running, the voltage at the cig lighter will go higher than 12v and I can't ascertain if that matters. Really don't want to fry the poor lappy (if I can help it).I was going to make up a jig to test volts/amp to monitor it for a charge cycle however Jaycar only sells the DC plug but not the socket so I'd have to find out how to get a DMM probe to somehow fit securely into the 'tip' on the plug of the AC charger. Any ideas?Does anyone have any experience connecting one of these to the car or know what the DC input voltage limits are for these machines?

author: saturation
author_rank: Super Contributor
timestamp: November 20, 2011, 12:29:47 pm
content: It would be safer to use the DC-AC inverter to your laptop AC-DC converter and finally to the laptop for several reasons; 3 levels of regulation and convenience. If you bring other appliances that have their own wall warts, you know they can be plugged into the inverter, and thus its ready to roll in your vehicle without more thought; the inverter is one-size fits all for all devices that use wall warts, even if its just a step down transformer. The key item is to get an inverter with enough power output to service all your devices.The inverter will take DC swings and insure its line voltage. Then the AC-DC laptop regulator have their own line regulation, in addition to DC voltage regulation, and often its UL, CSA or TUV certified for safe operation. Finally, the laptop/netbooks tend to have onboard DC-DC voltage regulator on the PCB too. Often you'll find yourself in an office or a hotel, and so you are already prepared to use the AC charger in the room to keep your laptop working.I've use this method for over a decade, as I carry many devices into off-road locations such as forests and state parks. Many 'third party' DC-DC regulators tend to come for dubious sources and often are not certified for safety, unlike the high volume laptops and their power supplies.

author: PetrosA
author_rank: Frequent Contributor
timestamp: November 20, 2011, 06:00:48 pm
content: When I carried my 1000H in my truck, I connected it directly to the power port. If the PC was off or in hibernation, it was fine under all conditions (engine off, starting, engine running) but if it was on, the OS sometimes froze while starting the engine. My simple workaround was to unplug it while starting the engine.

author: phil_jp1
author_rank: Regular Contributor
timestamp: November 21, 2011, 02:26:02 am
content: Quote from: PetrosA on November 20, 2011, 06:00:48 pmThose kind of devices is not protected from huge voltage spikes, that are present in a car!Connecting laptop straight to car 12V - it's like playing Russian Roulette.Normal car working voltage is about 13.2V - 14.8V and voltage spikes can reach in some cases hundreds of volts.So, your laptop can work just fine for some time, and one day it can (and probably will) just silently (or not so) die.

author: sonicj
author_rank: Frequent Contributor
timestamp: November 22, 2011, 05:02:35 am
content: i use a dc/dc converter for my macbook pro. inverter + factory charger is cumbersome, noisy & inefficient. like petros said, you could likely just fuse it and plug it in.check these:http://www.ebay.com/itm/DC-Car-Charger-Adapter-ASUS-EEE-PC-904-904HD-1000-1000H-/270401490909?pt=LH_DefaultDomain_0&hash=item3ef52f4fdd#ht_2259wt_907http://www.ebay.com/itm/Asus-Eee-PC-1000XP-1000H-1000HA-DC-adapter-car-charger-/190478353453?pt=LH_DefaultDomain_0&hash=item2c5965042d#ht_2926wt_907-sj

author: NiHaoMike
author_rank: Super Contributor
timestamp: November 22, 2011, 04:45:00 pm
content: Make a simple filter out of a large "car audio" cap, an inductor, and a LDO.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: November 29, 2011, 08:22:19 am
content: Sorry been away. Thanks for the tips, I've gone with the dc-dc gadget off ebay option. Hasn't got here yet. When it does I will chuck it on the bench and report back how it is for anyone interested. Thanks again.I still do not know the allowable parameters of the DC power input jack on the computer. I'll just have to assume it is 12v up to three amps and perhaps, asphil_jp1suggests, not so forgiving voltage wise.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: November 29, 2011, 08:34:08 am
content: Quote from: Ed.Kloonk on November 29, 2011, 08:22:19 amI had a chance to test one of these just yesterday, they work from 10.5 to 16 V without any problems, but that is just my experience. The most versatile is my main PC ViewSonic VOT120 nettop working from 8 to 30 V (originally specs say 18 V), so sometimes i just run it straight from solar panel or a 12 V battery.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: November 29, 2011, 08:48:05 am
content: Good to know.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: December 24, 2011, 10:05:10 pm
content: The 12v cig lighter adapter finally arrived. Seemed to take a long time from come from Honkers. Will be cranking it up on the bench soon to see what pops. Unfortunately, for the time being during Christmas and everything, I have to spend time with my family.