Car charger design

Started by hamilton in sci.electronics.design7 years ago 13 replies

I would like to find or build a car charger for my new tablet. The AC power is 9VDC @ 2A. Has anyone seen a car charger with these specs...

I would like to find or build a car charger for my new tablet. The AC power is 9VDC @ 2A. Has anyone seen a car charger with these specs ? Thanks for any hints. hamilton


Battery or charger

Started by Andy K in sci.electronics.design2 years ago 4 replies

My battery in my Alcatel phone will no longer charge. How can I tell if the charger is bad or the battery ? The charger connector is too...

My battery in my Alcatel phone will no longer charge. How can I tell if the charger is bad or the battery ? The charger connector is too small to test with a voltmeter. Thanks.


Unsmoothed car battery charger - is it crap?

Started by Eddie in sci.electronics.design8 years ago 150 replies

My car battery is oversized for the car. The battery is a bit old but usually works fine. The battery is flat (I left the lights on). ...

My car battery is oversized for the car. The battery is a bit old but usually works fine. The battery is flat (I left the lights on). My fancy new modern charger senses a poor battery and only puts in very little charge. I used to use a really old charger to charge this battery successfully. I opened up the old charger and saw it was only a transformer and a big rectifier. Tha...


How does this balance charger battery sensing work?

Started by John Doe in sci.electronics.design2 weeks ago 2 replies

My writing below the link might be more concise. I bought a "balance charger" that allegedly tries to evenly charge every cell in a battery...

My writing below the link might be more concise. I bought a "balance charger" that allegedly tries to evenly charge every cell in a battery pack. Apparently the individual cell voltages are correctly displayed. The battery pack to be charged has four wires. It is connected to the "balance charger" as in the links below. The balance charger has four sensing circuit leads, two of them ...


Charger

Started by HardySpicer in sci.electronics.design9 years ago 3 replies

I have a set of wireless headphones with a charger. the charger is the same size as the 240v mains plug! (it is the mains plug in fact...

I have a set of wireless headphones with a charger. the charger is the same size as the 240v mains plug! (it is the mains plug in fact - embedded into it). How is that done? I assume there is no transformer but to step the voltage down without much heat?? I assume the current is very low of course. H.


NiMH charger recommendations?

Started by DaveC in sci.electronics.design5 years ago 25 replies

First of all, this is a request for a *recommendation*, not a request for someone to do Google searches for me. - - - I need a charger for AA,...

First of all, this is a request for a *recommendation*, not a request for someone to do Google searches for me. - - - I need a charger for AA, AAA, and 9v batteries. Four of the AA or AAA at a time is OK. I see very few that support all these batteries (Maha makes a separate charger for 9v). Of those that do, not all use delta-V termination (or don't specify). Of those remaining th...


Why are cheap Nicads rejected by intelli-charger

Started by -dave- in sci.electronics.design7 years ago 9 replies

After only a few cycles, some very cheap AA NiCads I had bought were being rejected by my "intelligent" charger. Is there something about the...

After only a few cycles, some very cheap AA NiCads I had bought were being rejected by my "intelligent" charger. Is there something about the chemistry of these cells which causes them to present the wrong electrical characteristics for the charger?


NiCad Charger Question

Started by Chris in sci.electronics.design8 years ago 14 replies

I need to make a slow charger for a 24V NiCad pack. I was thinking of using a 12V regulator IC to provide a constant current to the...

I need to make a slow charger for a 24V NiCad pack. I was thinking of using a 12V regulator IC to provide a constant current to the battery pack @ 20mA. I do not need a timer or peak deltaV detection, just a ~15Hr charger. Here is the schematic: http://chrismaness.com/backend/tCad2.png Will this work? Regards, Chris


2 cell, linear li-ion poly charger ic recommendation?

Started by Lee in sci.electronics.design6 years ago

anybody knows a good linear charger ic to charger 2 cell li-poly? capacity around 50wh. integrated fet preferred. thanks.

anybody knows a good linear charger ic to charger 2 cell li-poly? capacity around 50wh. integrated fet preferred. thanks.


usb charger schematic?

Started by bob in sci.electronics.design6 years ago 11 replies

"Wall wart" charger used to be large because they contain an AC transformer. Recently, cellphone and usb chargers have become smaller and...

"Wall wart" charger used to be large because they contain an AC transformer. Recently, cellphone and usb chargers have become smaller and lighter than a typical transformer, yet they usually work with world voltages (110 to 240). How do they do it? I opened up a cheap no brand usb charger and found some discrete components (transistors, capacitors, resistors, ...), and a tiny transform...


Adding a 6v boost to a 12v battery charger

Started by Too_Many_Tools in sci.electronics.design8 years ago 26 replies

I have access to a Schumacher wheeled battery charger that is 12 v only. I want to use its boost feature (200amp) on 6 volt systems. Any...

I have access to a Schumacher wheeled battery charger that is 12 v only. I want to use its boost feature (200amp) on 6 volt systems. Any suggestions as to how to make a mod where the charger will do both 12v and 6v? I have looked and have not found any schematics. I am assuming that any mods will be downstream of the transformer. Thanks for any suggestions. TMT


Li-Ion questions (charger, fast-cycling)

Started by Joerg in sci.electronics.design12 months ago 14 replies

Hi Folks, Just bought another Li-Ion deal with charger: https://images-na.ssl-images-amazon.com/images/I/41HL6Xmx1qL._SX466_.jpg The...

Hi Folks, Just bought another Li-Ion deal with charger: https://images-na.ssl-images-amazon.com/images/I/41HL6Xmx1qL._SX466_.jpg The charger is like this little guy, a switcher that can deliver 1 amp: https://images-na.ssl-images-amazon.com/images/I/41HL6Xmx1qL._SX466_.jpg The typical battery is two cell bundles in series so 8.4V max. To my surprise the charger has 10.2V open loop...


Heliotropic tracker

Started by Chris in sci.electronics.design1 year ago 58 replies

Say I have (for example) a cellphone charger that uses sunlight to charge the phone. The phone and charger are in an attic room with one small...

Say I have (for example) a cellphone charger that uses sunlight to charge the phone. The phone and charger are in an attic room with one small roof window so as the sun moves around the sky, the small patch of sunlight slowly creeps from one side of the floor to the other. How could one best implement a mechanism to track the sun's movement and keep that charger in the sunny patch at all...


Forever Power (almost)

Started by Anonymous in sci.electronics.design4 months ago 27 replies

This is just a stupid idea that I had, which will acomplish nothing, other than see how long it lasts. I dont know how much a standard 12V 5...

This is just a stupid idea that I had, which will acomplish nothing, other than see how long it lasts. I dont know how much a standard 12V 5 amp battery charger requires from the 120Vac power line, but I read it was around 150 watts. So, lets say I connect a 200W inverter to a car battery. Then plug into that inverter, a 12V 5A battery charger, and connect the leads from that charger to...


Charger for SLA 12V / 7Ah battery

Started by gm in sci.electronics.design2 years ago 32 replies

The subject says all :-) I connected 3 x 12V / 7Ah battery's is serial and start to charge them with my ebike 36V/1,2A charger. After cca 30...

The subject says all :-) I connected 3 x 12V / 7Ah battery's is serial and start to charge them with my ebike 36V/1,2A charger. After cca 30 minutes battery pack was getting hot, so i disconnect the whole stuff. What is the highest charging current for such battery's ? The funny thing is that i use the same charger to recharge my 36V ebike battery pack, and there was no problems whats...


Will a dimmer switch work instead of an incandescent light bulb in a simple battery charger?

Started by Anonymous in sci.electronics.design4 years ago 42 replies

The other day, I came upon this: http://www.alpharubicon.com/elect/3dollarb= attggn.htm It's plans for a very simple battery charger that uses...

The other day, I came upon this: http://www.alpharubicon.com/elect/3dollarb= attggn.htm It's plans for a very simple battery charger that uses a light bulb and dio= de in series to make a constant current battery charger. Benefits include p= ulse charging for desulfation and the fact that it can charge batteries of = any voltage. Well, with incandescent light bulbs getting scarce and me ...


Charge 2 x 6V on 12V Charger

Started by Olin Frank in sci.electronics.design6 years ago 117 replies

If I have two 6V SLA's of the same brand, capacity, and past usage, can I safely series wire them to charge with my existing 12V charger? Olin...

If I have two 6V SLA's of the same brand, capacity, and past usage, can I safely series wire them to charge with my existing 12V charger? Olin Frank


solar cell charger

Started by SANTU in sci.electronics.design9 years ago 4 replies

hello friends iwant some help to make solar cell charger.pls help me out if u have any idea on this project .mail to santugoal@gmail.com.

hello friends iwant some help to make solar cell charger.pls help me out if u have any idea on this project .mail to santugoal@gmail.com.


Charge gel cell with car charger?

Started by Mike Cook in sci.electronics.design5 years ago 89 replies

A friend has a battery powered Ryobi lawn trimmer ("weed whacker") which doesn't work. The 12vdc wall wart puts out only ~ 12.4v. I charged...

A friend has a battery powered Ryobi lawn trimmer ("weed whacker") which doesn't work. The 12vdc wall wart puts out only ~ 12.4v. I charged the lead-acid gel cell using a car charger. The charge rate (selectable) was 0.5A. Afterward the trimmer seemed to work as new. Can the car charger be used to charge this battery? He can install a timer to limit charge time if that's something req...


Trickle charger advice

Started by Alexander Avtanski in sci.electronics.design9 years ago 16 replies

Hello, I'm working on a hobby project (something like a really fancy timer). The thing will be powered mostly from the grid, but when...

Hello, I'm working on a hobby project (something like a really fancy timer). The thing will be powered mostly from the grid, but when necessary I should be able to unplug it and use it on internal power. My plan is to use a rechargeable NiMH 9V battery, that is being kept topped off by a trickle charger when the thingy is plugged in (that would be, like, over 95% of the time). I don't ...