Hello all,
I'm new on the forum, so let's briefly introduce myself so you can understand better my question.
I am electronics designer, I work for an automotive electronics company providing oem electronics devices to car manufacturers.
I work on some products that shall be able to fast-charge "any smartphones" on the market.
I understood that most of the big smartphone manufacturers are participating to some workgroups to define a universal charger. These initiatives seems to rely on the "battery charging specification" from USB-IF.
But we are talking about AC charger here, there is no data communication and I guess it will use "DCP" profile from BCS. DCP is Dedicated Charger Port.
On my side, I would like to offer both fast-charge and data connection.
Then I plan to use CDP mode from BCS. CDP is Charging Downstream Port, it allows both data com and charging at same time.
This looks good by I dont have a clue if CDP mode is supported by smartphones and tablets on the market.
If anybody can confirm CDP support for some manufacturers or some models, I would appreciate a lot !
Best regards,
I would be very, very, very interested in knowing the answer to this question too. I think at some point wm6 phones could be hacked to draw more than 500mA from a USB port, but doubt modern OSes allow that ...
Related
Hi everyone ...
I have a new car on order, delivery in a few months, and have taken the option of Multimedia screens for the second row passengers.
These are just the screens though with analog inputs (composite, RCA, whilte-red-yellow, .... what's in a name ).
Image here : http://goo.gl/90Nr1o
I am looking for two devices to use in the car to watch movies (and if possible play games) to entertain the kids on long trips (5 & 8 years of age).
Power requirements need to be quite low though since these have to run from the 12V cigarette lighter.
My first idea was to run a pair of Raspberry Pi's with RaspBMC and Retropie on them, add a BT and a Wifi adapter, put a small router with an HDD in the trunk and configure them with a PS3 wireless controller. It does require quite some fiddling, setup and troubleshooting in order to get all of this working though ...
Secondly I was thinking of an Ouya + XMBC on it ..; but this doesn't have an analog output ...
Next in line I turn myself to Android devices which could prove great candidates for my intended use, but I am completely lost in the vast amount of devices available ... especially the ones which could tick all the boxes.
All advice and experiences would be greatly appreciated !
MaXX99 said:
Hi everyone ...
I have a new car on order, delivery in a few months, and have taken the option of Multimedia screens for the second row passengers.
These are just the screens though with analog inputs (composite, RCA, whilte-red-yellow, .... what's in a name ).
Image here : http://goo.gl/90Nr1o
I am looking for two devices to use in the car to watch movies (and if possible play games) to entertain the kids on long trips (5 & 8 years of age).
Power requirements need to be quite low though since these have to run from the 12V cigarette lighter.
My first idea was to run a pair of Raspberry Pi's with RaspBMC and Retropie on them, add a BT and a Wifi adapter, put a small router with an HDD in the trunk and configure them with a PS3 wireless controller. It does require quite some fiddling, setup and troubleshooting in order to get all of this working though ...
Secondly I was thinking of an Ouya + XMBC on it ..; but this doesn't have an analog output ...
Next in line I turn myself to Android devices which could prove great candidates for my intended use, but I am completely lost in the vast amount of devices available ... especially the ones which could tick all the boxes.
All advice and experiences would be greatly appreciated !
Click to expand...
Click to collapse
CS918 has this output function.
I'd say you'd want an Android Stick rather than Box though as I doubt a 12V would be able to power a full box.
Hammer_drum said:
CS918 has this output function.
I'd say you'd want an Android Stick rather than Box though as I doubt a 12V would be able to power a full box.
Click to expand...
Click to collapse
Hi Hammer ...
Problem with sticks is that most rely solely on HDMI output. AV-Out is mostly not an option on most.
Furthermore, these run the same chipsets as their box counterpart and consome probably only marginally less power.
The CS968 comes with a 5V 3A adapter --> Max 15W
The MK902 with a 5V 2.5 adapter --> Max 12.5 W
I do not know how much power can be drawn from a single 12V socket, but I found an adapter which could deliver 2 X 12W (2 x 2.4A), which - I think - could be sufficient to power 2 boxes ? Normally the power adapter should be sided marginally larger than the max power drain ... I hope
http://www.scosche.com/ipad-usb-car-charger-two-port
I also found an even more powerful adapter capable of delivering 6A ...
And it seems like a higher power version with 8A is under way
http://saicoo-tech.com/html/product/view-2342.html
I thought it is a common question to ask how much current can a mobile device that supports USB host mode deliver at max, but I couldn't find any satisfying answer. I know traditional USB port on PC can usually deliver 500 mA at max, tablets or mobile devices that support USB host mode or OTG functionality may possibly cannot supply that much current.
Do you have any idea how much current a tablet, say Samsung Galaxy Tab, can deliver current at max? It may depend on brand and model. If so, can you please give me some examples?
I am gonna buy mobile RFID reader however, that module can draw current up to 500mA, around 2.5 Watts, and wondering if tablet can supply that much or not..
Any ideas greatly appreciated
I've been wanting to get one of those game controllers for my LG G4, that the phone clips onto/fits into, but I'm unsure about the technology.
The ones I've seen fall into three categories:
Bluetooth. Most of the gamepads designed for phones seem to be Bluetooth (probably because it was available sooner). I really don't like the idea - in my experience, Bluetooth is super unreliable, and it seems awfully wasteful to use a power-hungry radio connection to an accessory that's physically touching the phone.
NFC. Seems like maybe less wasteful (I don't know how much power NFC draws, but I imagine it's less than Bluetooth), but I've only seen them for Samsung devices. Do they exist for other brands? Are they any better in terms of battery draw and reliability? Can NFC even be used for that sort of long-term connection or is Samsung doing something special to make it work?
USB. As I understand, on most phones today the USB port works as both a client (to connect to a PC) and, with the right cable, a host (to connect other devices to the phone)? So it should be possible to connect an ordinary USB gamepad? I feel like that would be the most reliable (no wireless interference) and efficient (no radio), though USB can be fairly power hungry too... Anyway I've never seen gamepads designed for phones that use USB, either.
So, do USB or NFC gamepads exist that are designed to hold a phone? Do they work with the G4? Which technology is better?
I am currently getting interested to the topic of bidirectional e-coupled technology in order to allow battery charge sharing between smartphones in an inductive way. I know that there are some solutions for the smartphone-charging pad method but none for the smartphone-smartphone approach. I therefore guess that the critical issue is to make the smartphone be not only a receiver but also a host in this receiver/host model. But I have no clue. Anyone knows how can I develop this solution?
Developing products that plug into phones and communicate via USB, and I'd really love to know if there are phones out there that limit their output current to less than 500 mA, but I have no idea how to find this information.
I've been searching for a long time and the only clue I have found so far is that some Sony Xperia phones will pop up a "USB power consumption error", so presumably they have a current limitation, but I don't know what it is in mA. Is this a Sony-only error message or built into Android? Is there a similar message built into Android that could help me find instances of this?
I've also tested S6, S7, Pixel with a device that claims 250 mA and they all support it. (Pixel seems to disconnect power from it or put it to sleep after 4 seconds of being unused, similar to "USB selective suspend" on a PC, which is fine.)
endolith said:
Developing products that plug into phones and communicate via USB, and I'd really love to know if there are phones out there that limit their output current to less than 500 mA, but I have no idea how to find this information.
I've been searching for a long time and the only clue I have found so far is that some Sony Xperia phones will pop up a "USB power consumption error", so presumably they have a current limitation, but I don't know what it is in mA. Is this a Sony-only error message or built into Android? Is there a similar message built into Android that could help me find instances of this?
I've also tested S6, S7, Pixel with a device that claims 250 mA and they all support it. (Pixel seems to disconnect power from it or put it to sleep after 4 seconds of being unused, similar to "USB selective suspend" on a PC, which is fine.)
Click to expand...
Click to collapse
U could limit the mA by yourself u need a special tool for it. but its root, why u especially need less than 500mA
Tekodrink said:
U could limit the mA by yourself u need a special tool for it. but its root, why u especially need less than 500mA
Click to expand...
Click to collapse
Well I'm looking for information about *all* phones, not just ones I can test myself.
I have an S6, S7, Pixel, and some older Android phones like G2 and Relay. I'd like to know what's out there in terms of current capability.
In other words, if my device requests 500 mA, will it not work on certain phones or do they all support that now?
The current regulation used to be limited , however in the kernel the values could be edited to go above the officially admitted values, this was done in older phones to obtain a "fast charge" and in other cases the overclocking the CPU of the phone a bit more.
Regarding the 500mA current, I * BELIEVE * that after Android 2.3 all phones support 500mA as Standard * HOWEVER, the compatibility of accessories could be limited by the manufacturer such as the moto g6 , that does not work with some usb cables c although the cables have enough current and worked on other phones or even other motorola devices.
Considering the number of devices you've tested them on, I'd say it should work
ThatLatinGuy said:
this was done in older phones to obtain a "fast charge"
Click to expand...
Click to collapse
I'm talking about current from the phone, not to the phone.
endolith said:
I'm talking about current from the phone, not to the phone.
Click to expand...
Click to collapse
It only delivers anything when in USB-OTG mode. This isn't as well-known as normal USB. This article describes USB-OTG power in more detail.
The OTG spec calls for at least 8mA and allows negotiation for higher currents if the peripheral needs more power. OTG devices can provide up to 500mA, but in realistic terms, handheld portable electronics don't have 500mA to spare for external loads. 100mA is a commonly accepted realistic maximum.
src: https://electronics.stackexchange.c...current-can-an-android-phones-usb-port-supply
Yes, the limit for a given phone is somewhere between 8 mA and 500 mA. I would like to know how common it is for a phone to have that limit set to less than 500 mA