Power from USB & DC Adapter (was Re: Design Files/Gerbers of SAKC V2)

Carlos Camargo cicamargoba at gmail.com
Fri Jul 30 12:05:02 EDT 2010


Adam,

I've already change D8, D9 D10 footprints, and add the indication about DC
jack polarity. The gerbers are in the ORCAD_design_files directory on git
repository


Carlos





On Fri, Jul 30, 2010 at 11:01 AM, Carlos Camargo <cicamargoba at gmail.com>wrote:

> [1]http://arduino.cc/en/Main/ArduinoBoardDuemilanove
>
> We will ti use a similar design for +5V collide protection. But this
> circuit has problems with low level voltages, under 5V
>
> Carlos
>
>
>
> On Fri, Jul 30, 2010 at 10:50 AM, David Reyes Samblas Martinez <
> david at tuxbrain.com> wrote:
>
>> I forget to add the link.
>>
>> 2010/7/30 David Reyes Samblas Martinez <david at tuxbrain.com>:
>> > 2010/7/30 Carlos Camargo <cicamargoba at gmail.com>:
>> >
>> >> Arduino for example, works with 5V,
>> > Wrong, the most common board "duemilanove":
>> > from his specification page[1]
>> > Operating Voltage       5V
>> > Input Voltage (recommended)     7-12V
>> > Input Voltage (limits)  6-20V
>> >
>> > it only use 5V as input when powered though USB,
>> >
>> > I you have a 5V power source you can use the USB plug to avoid the 6V
>> > input limitation on Vin,
>> >
>> >
>> >> I think that the daughter card will have the specific power supply, so
>> we
>> >> can reduce the SAKC complexity and maintain the flexibility.
>> > ok I can agree in fact "low" voltage from higher to 5V is no a big
>> > deal, a voltage regulator before the plug can fit for an especific
>> > aplication. rising voltage is allways more complicated.
>> >>
>> >>
>> >> Carlos
>> >>
>> >>
>> >>
>> >> On Fri, Jul 30, 2010 at 10:17 AM, David Reyes Samblas Martinez
>> >> <david at tuxbrain.com> wrote:
>> >>>
>> >>> I must agree with Ron that we don't have to save in "poka yokes" on
>> >>> the power sourcing on SACK
>> >>> +1 to the  +/- protection
>> >>> +1 to the +5V collide protection
>> >>>
>> >>> and how much cost and space is for the power regulator?
>> >>>
>> >>> 2010/7/30 Ron K. Jeffries <rjeffries at gmail.com>:
>> >>> > Please make sure that the design protects
>> >>> > against plus and minus being plugged in wrong.
>> >>> > I think that implies a zener diode.
>> >>> > the extra cost of a 5V supply that accepts a fairly
>> >>> > wide range of input voltage say 12v or less
>> >>> > is probably worth it IMO
>> >>> > SAKC is prolly less price sensitive than Nanonote.
>> >>> > ---
>> >>> > Ron K. Jeffries
>> >>> > http://ronkjeffries.posterous.com
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> >
>> >>> > On Fri, Jul 30, 2010 at 07:44, Carlos Camargo <
>> cicamargoba at gmail.com>
>> >>> > wrote:
>> >>> >>
>> >>> >> Hi Adam
>> >>> >>
>> >>> >>
>> >>> >>
>> >>> >> On Fri, Jul 30, 2010 at 8:53 AM, Adam Wang <adam at sharism.cc>
>> wrote:
>> >>> >>>
>> >>> >>> Hi,
>> >>> >>>
>> >>> >>> 1, I made a mistake on D10 footprint confirmation, It must be 0805
>> to
>> >>> >>> meet MSCD104H. Pls change this to 0805 package.
>> >>> >>
>> >>> >> ok, I'll fix it
>> >>> >>
>> >>> >>
>> >>> >>>
>> >>> >>> 2, maybe mark a concentric circles with central ring to mark "+"
>> and
>> >>> >>> outer ring marked a "-" nearby DC Jack to suffer from mistakes by
>> >>> >>> novices.
>> >>> >>
>> >>> >> Agree
>> >>> >>
>> >>> >>>
>> >>> >>> 3, last but not least, current design of SAKC V2 have a condition
>> that
>> >>> >>> is
>> >>> >>> it can not use +5V power at the same time either from USB cable
>> >>> >>> (0.5A) or DC
>> >>> >>> adapter(can be more). If using DC adapter fixed +5V in already,
>> >>> >>> you must _remember_ to take out mini-jumper on J18 first, then
>> plug-in
>> >>> >>> usb
>> >>> >>> cable to do s/w work. If you forgot that take out mini-jumper,
>> after
>> >>> >>> plugging usb cable; There must be have power +5V "collide"
>> together.
>> >>> >>> This
>> >>> >>> UNSAFE condition will be happened once mindless to forget to take
>> out
>> >>> >>> mini-jumper. And possibly let USB host device to be have damage or
>> >>> >>> even DC
>> >>> >>> adapter source. Also if remove DC adapter, the SAKC it can only
>> get
>> >>> >>> 0.5A
>> >>> >>> from usb, unworthy a bit. so
>> >>> >>>
>> >>> >>> 1) remove the DC adapter reducing the hardware hacking usability
>> of
>> >>> >>> the
>> >>> >>> board a lot.
>> >>> >>
>> >>> >>
>> >>> >>>
>> >>> >>> 2) remove USB power, adding the need for an extra power adapter
>> for
>> >>> >>> every
>> >>> >>> user.
>> >>> >>
>> >>> >>
>> >>> >>>
>> >>> >>> 3) add additional circuitry to make both USB & DC power stable in
>> all
>> >>> >>> cases. User should have the chance to update s/w from USB while
>> still
>> >>> >>> some
>> >>> >>> h/w parts connected to SAKC board's extendable 40pins header to
>> get
>> >>> >>> 3.3V
>> >>> >>> supply( actually comes from 5V) to outside application.
>> >>> >>
>> >>> >> Yes, I'm trying to solve this issue, I think that we can use a
>> single
>> >>> >> circuit Power On Reset + Transistor:
>> >>> >>                             TRANSISTOR
>> >>> >> USB_VCC-------------|S|           |D|----------- 5V
>> >>> >>                                                        |
>> >>> >>                                      |G|              |
>> >>> >>                                        |               |
>> >>> >> DC_WALL------|  POR |----------------------
>> >>> >>
>> >>> >>
>> >>> >> When DC_WALL = 0V  Transistor is ON so 5V = USB_VCC
>> >>> >> when DC_WALL >= POR's threshold => Transistor is OFF =>  5V =
>> DC_WALL
>> >>> >>
>> >>> >>>
>> >>> >>> Also if SAKC comes with capability of having strong wide power
>> range
>> >>> >>> input, this can make/let additional circuities connected to SAKC
>> >>> >>> easiler and
>> >>> >>> more flexible with ONLY one DC adapter. Fg. real ROBOT industries
>> >>> >>> works
>> >>> >>> around +12V or +9V supply. IMO if this can be true. SAKC will be
>> more
>> >>> >>> stronger. Surely aside from cost evaluation.
>> >>> >>
>> >>> >> We can't provide all the possible voltages for all the possible
>> >>> >> applications. We can add an additional 5v regulator with a wide
>> input
>> >>> >> range,
>> >>> >> but this increase the cost & the size.
>> >>> >> Carlos
>> >>> >>
>> >>> >>
>> >>> >> --
>> >>> >> Carlos Iván Camargo Bareño
>> >>> >> Profesor Asistente
>> >>> >> Departamento de Ingeniería Eléctrica y Electrónica
>> >>> >> Universidad Nacional de Colombia
>> >>> >> cicamargoba at unal.edu.co
>> >>> >>
>> >>> >> _______________________________________________
>> >>> >> Qi Developer Mailing List
>> >>> >> Mail to list (members only): developer at lists.qi-hardware.com
>> >>> >> Subscribe or Unsubscribe:
>> >>> >> http://en.qi-hardware.com/mailman/listinfo/developer
>> >>> >
>> >>> >
>> >>> > _______________________________________________
>> >>> > Qi Developer Mailing List
>> >>> > Mail to list (members only): developer at lists.qi-hardware.com
>> >>> > Subscribe or Unsubscribe:
>> >>> > http://en.qi-hardware.com/mailman/listinfo/developer
>> >>> >
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> David Reyes Samblas Martinez
>> >>> http://www.tuxbrain.com
>> >>> Open ultraportable & embedded solutions
>> >>> Ben NanoNote, Arduino, Openmoko
>> >>> Hey, watch out!!! There's a linux in your pocket!!!
>> >>>
>> >>> _______________________________________________
>> >>> Qi Developer Mailing List
>> >>> Mail to list (members only): developer at lists.qi-hardware.com
>> >>> Subscribe or Unsubscribe:
>> >>> http://en.qi-hardware.com/mailman/listinfo/developer
>> >>
>> >>
>> >>
>> >> --
>> >> Carlos Iván Camargo Bareño
>> >> Profesor Asistente
>> >> Departamento de Ingeniería Eléctrica y Electrónica
>> >> Universidad Nacional de Colombia
>> >> cicamargoba at unal.edu.co
>> >>
>> >> _______________________________________________
>> >> Qi Developer Mailing List
>> >> Mail to list (members only): developer at lists.qi-hardware.com
>> >> Subscribe or Unsubscribe:
>> >> http://en.qi-hardware.com/mailman/listinfo/developer
>> >>
>> >
>> >
>> >
>> > --
>> > David Reyes Samblas Martinez
>> > http://www.tuxbrain.com
>> > Open ultraportable & embedded solutions
>> > Ben NanoNote, Arduino, Openmoko
>> > Hey, watch out!!! There's a linux in your pocket!!!
>> >
>>
>>
>>
>> --
>> David Reyes Samblas Martinez
>> http://www.tuxbrain.com
>> Open ultraportable & embedded solutions
>> Ben NanoNote, Arduino, Openmoko
>> Hey, watch out!!! There's a linux in your pocket!!!
>>
>> _______________________________________________
>> Qi Developer Mailing List
>> Mail to list (members only): developer at lists.qi-hardware.com
>> Subscribe or Unsubscribe:
>> http://en.qi-hardware.com/mailman/listinfo/developer
>>
>
>
>
> --
> Carlos Iván Camargo Bareño
> Profesor Asistente
> Departamento de Ingeniería Eléctrica y Electrónica
> Universidad Nacional de Colombia
> cicamargoba at unal.edu.co
>



-- 
Carlos Iván Camargo Bareño
Profesor Asistente
Departamento de Ingeniería Eléctrica y Electrónica
Universidad Nacional de Colombia
cicamargoba at unal.edu.co
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