You can use the same part as Q2 out any other logic level nFET (e.g. BS170). This is the wrong thread for this discussion, and I see you started another thread. Let's continue there. On Feb 13, 2014 9:44 AM, "fabrio pellegrinetti" <[email protected]> wrote:
> > <https://lh6.googleusercontent.com/-asg5M3zqtDM/Uvz-AcR0ouI/AAAAAAAAAo8/Gm-C7M52jpE/s1600/host.jpg> > > Sorry, torow the pin 40 I can't drive the FET Q2 how I need the > > I'm sorry for the disturb: between the pin 40, It's impossible to drive > the FET Q2 how I need, for to change charge current . > > Your solution, is the best. > > Wich type of Fet you suggest me to use? > > > grazie > > > On Thursday, February 13, 2014 5:39:27 PM UTC+1, Ytai wrote: >> >> Sorry, I can't really understand what you're asking / suggesting. >> Which pin 40 are you talking about and what exactly do you want to do >> with it? >> I don't think the fuse can easily be destroyed. It is resettable. >> >> >> On Thu, Feb 13, 2014 at 6:15 AM, fabrio pellegrinetti >> <[email protected]>wrote: >> >>> Thanks Ytai. >>> >>> The solution you propose is very interesting. >>> But is there a simpler solution? >>> Is there a way to intervene by software to change the state of pin 40 of >>> the PIC24F? >>> I want to change the state of pin 40 to act on the FET Q2 so as to >>> dynamically change the VBus. >>> From java programming or modification to the firmware? >>> Looking at the diagram IOIO-OTG, I noticed that one pin of switch_spdt >>> is marked with "U4", but I can not find a match. >>> Maybe I'll go OT: surely I've burned the fuse of ioio. >>> Could you tell me what this fuse on the board and its spefifiche to buy >>> new and replace it? >>> >>> Thank you for the wonderful device that you created Ytai >>> >>> On Tuesday, February 11, 2014 5:48:38 PM UTC+1, Ytai wrote: >>> >>>> OK, I think I understand now. I don't think you need a digital >>>> potentiometer for that. Look at the IOIO-OTG schematic and identify Q1. It >>>> is a p-Channel FET responsible for the power supply on the VBUS line. When >>>> the IOIO is in device mode, its gate is left floating, and thus gets pulled >>>> up by R3 and the FET is not conducting. >>>> >>>> When in host mode, the PIC will pull the gate low through Q2 and R3. >>>> According to the setting of R3, the gate voltage will vary, which can be >>>> used to put Q1 in linear mode, so that it acts as a resistor on VBUS and >>>> limits charging current. >>>> >>>> All you're missing, it being able to pull Q1's gate directly to GND in >>>> order to supply full current when your main supply is up. You can probably >>>> just extract a single wire from the leg of the chip, and connect it through >>>> an n-FET to GND, where the n-FET gate will be driven by a signal that tells >>>> you that your main supply is good. >>>> >>>> >>>> On Tue, Feb 11, 2014 at 2:23 AM, fabrio pellegrinetti <[email protected] >>>> > wrote: >>>> >>>>> Thanks for the answers. >>>>> >>>>> let me try to explain better...what I would need on the ioio is to >>>>> control the vbus with a digital potenziometer ioio embedded (controlled by >>>>> java) instead of the standard one because I need to mantain the usb >>>>> connection always active. >>>>> When the power line is present, I need to put via software the vbus at >>>>> the maximum value for the android recharge, while when the power line is >>>>> off the system needs to use the backup battery. In this case the vbus has >>>>> to go to the minimum in order to continue to use the usb connection. >>>>> >>>>> So, I need an hardware change on the ioio. >>>>> >>>>> >>>>> >>>>> >>>>> On Friday, February 7, 2014 11:09:30 PM UTC+1, Ytai wrote: >>>>> >>>>>> Such a FET already exists in the IOIO-OTG, however, this will also >>>>>> cause the USB connection to get dropped, which is I assume not what is >>>>>> desired in this case. >>>>>> On Feb 7, 2014 9:06 AM, "Nishant Sood" <[email protected]> wrote: >>>>>> >>>>>>> Fabrio, >>>>>>> >>>>>>> If you want to control charging of the android programmatically (in >>>>>>> the hardware it cuts off only when full charge automatically) then I >>>>>>> would >>>>>>> suggest controlling the power going to the android controlled using a >>>>>>> power >>>>>>> mosfet switched programmatically when you sense the system has gone to >>>>>>> battery backup >>>>>>> >>>>>>> >>>>>>> On Fri, Feb 7, 2014 at 10:28 PM, Ytai Ben-Tsvi <[email protected]>wrote: >>>>>>> >>>>>>>> I don't know if there's a programmatic way to disable charging on >>>>>>>> the Android. >>>>>>>> What you *can* do, however, is detect the power fault condition >>>>>>>> and put the phone to sleep. It should take very little current at this >>>>>>>> mode, assuming the battery was previously fully charged. >>>>>>>> >>>>>>>> >>>>>>>> On Fri, Feb 7, 2014 at 7:49 AM, fabrio pellegrinetti < >>>>>>>> [email protected]> wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> hello to all. >>>>>>>>> during the development of my home automation project, I came >>>>>>>>> across the problem of the power supply of Android and ioio which must >>>>>>>>> be >>>>>>>>> separated. >>>>>>>>> my board provide power supply of 14V 2A with a transformer 220V >>>>>>>>> to 14V and one backup battery of 1200mAh and 12V recharged from the >>>>>>>>> transformer. >>>>>>>>> When the the power line is off, the battery must supply power at >>>>>>>>> the ioio, but he mustn't to the android. >>>>>>>>> For now I use Y split cable power supply double USB A and one usb >>>>>>>>> micro. >>>>>>>>> >>>>>>>>> Micro usb connected to the android, first usb to ioio and second >>>>>>>>> usb to another standard android power supply. the poteziometer Vbus >>>>>>>>> is >>>>>>>>> set to minimum in accord to the usb debug survey. >>>>>>>>> Problem is when the system goes on battery the an amount of mA >>>>>>>>> goes to the standard android power supply and this reduce backup >>>>>>>>> battery >>>>>>>>> charge >>>>>>>>> What I would like is to be able to check the current Vbus, from >>>>>>>>> java code from a ioio embedded digital potenziometer. >>>>>>>>> >>>>>>>>> so when detect power failure, I can dinamically reduce Vbus >>>>>>>>> current. >>>>>>>>> >>>>>>>>> thanks >>>>>>>>> best regards >>>>>>>>> >>>>>>>>> fabrio >>>>>>>>> >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "ioio-users" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to [email protected]. >>>>>>>>> To post to this group, send email to [email protected]. >>>>>>>>> >>>>>>>>> Visit this group at http://groups.google.com/group/ioio-users. >>>>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to a topic in >>>>>>>> the Google Groups "ioio-users" group. >>>>>>>> To unsubscribe from this topic, visit https://groups.google.com/d/ >>>>>>>> topic/ioio-users/s_NY9im_SVY/unsubscribe. >>>>>>>> To unsubscribe from this group and all its topics, send an email >>>>>>>> to [email protected]. >>>>>>>> To post to this group, send email to [email protected]. >>>>>>>> >>>>>>>> Visit this group at http://groups.google.com/group/ioio-users. >>>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> *Thanks & Regards,* >>>>>>> >>>>>>> *Nishant Sood* >>>>>>> *--* >>>>>>> *CEO and Founder* >>>>>>> >>>>>>> *Winacro Innovation's Inc.* >>>>>>> *----------------------------------------* >>>>>>> *www.winacro.com <http://www.winacro.com>* >>>>>>> *----------------------------------------* >>>>>>> *Contact's:* >>>>>>> *Mobile: +91-8447476798* >>>>>>> *Phone: 0129-4176798* >>>>>>> *Email: [email protected]* >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "ioio-users" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> To post to this group, send email to [email protected]. >>>>>>> >>>>>>> Visit this group at http://groups.google.com/group/ioio-users. >>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>> >>>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "ioio-users" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To post to this group, send email to [email protected]. >>>>> Visit this group at http://groups.google.com/group/ioio-users. >>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>> >>>> >>>> -- >>> You received this message because you are subscribed to the Google >>> Groups "ioio-users" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To post to this group, send email to [email protected]. >>> Visit this group at http://groups.google.com/group/ioio-users. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >> >> -- > You received this message because you are subscribed to the Google Groups > "ioio-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/ioio-users. > For more options, visit https://groups.google.com/groups/opt_out. > -- You received this message because you are subscribed to the Google Groups "ioio-users" group. 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