Hi all,
I was just wondering if I have a unit running on a battery how I can swap the
supply voltage with the VBUS when the MSP430F5529 is connected to PC through the
USB interface? I know to connect the battery and the VBUS together through
diodes. There is a disadvantage this way which drops the battery voltage by
0.4V. Any suggestion would be appreciated.
Thanks,
John.
VBUS on MSP430F5529
Started by ●January 7, 2013
Reply by ●January 7, 20132013-01-07
Use a P Channel MOSFET.
On Mon, Jan 7, 2013 at 2:27 AM, John wrote:
> **
> Hi all,
>
> I was just wondering if I have a unit running on a battery how I can swap
> the supply voltage with the VBUS when the MSP430F5529 is connected to PC
> through the USB interface? I know to connect the battery and the VBUS
> together through diodes. There is a disadvantage this way which drops the
> battery voltage by 0.4V. Any suggestion would be appreciated.
>
> Thanks,
>
> John.
>
>
>
--
Lu Filipe Rossi
Electrical Engineer
Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
Escola Politnica
Universidade de S Paulo
Cel. +55 (11) 7662-9234
On Mon, Jan 7, 2013 at 2:27 AM, John wrote:
> **
> Hi all,
>
> I was just wondering if I have a unit running on a battery how I can swap
> the supply voltage with the VBUS when the MSP430F5529 is connected to PC
> through the USB interface? I know to connect the battery and the VBUS
> together through diodes. There is a disadvantage this way which drops the
> battery voltage by 0.4V. Any suggestion would be appreciated.
>
> Thanks,
>
> John.
>
>
>
--
Lu Filipe Rossi
Electrical Engineer
Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
Escola Politnica
Universidade de S Paulo
Cel. +55 (11) 7662-9234
Reply by ●January 7, 20132013-01-07
Isn't it necessary to control the mosfet gate? I guess it is not that
simple as to replace a diode by a mosfet.
2013/1/7 Luis Filipe Rossi
> Use a P Channel MOSFET.
>
> On Mon, Jan 7, 2013 at 2:27 AM, John wrote:
>
> > **
> >
> >
> > Hi all,
> >
> > I was just wondering if I have a unit running on a battery how I can swap
> > the supply voltage with the VBUS when the MSP430F5529 is connected to PC
> > through the USB interface? I know to connect the battery and the VBUS
> > together through diodes. There is a disadvantage this way which drops the
> > battery voltage by 0.4V. Any suggestion would be appreciated.
> >
> > Thanks,
> >
> > John.
> >
> >
> > --
> Lu Filipe Rossi
> Electrical Engineer
> Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> Escola Politnica
> Universidade de S Paulo
> Cel. +55 (11) 7662-9234
>
>
>
simple as to replace a diode by a mosfet.
2013/1/7 Luis Filipe Rossi
> Use a P Channel MOSFET.
>
> On Mon, Jan 7, 2013 at 2:27 AM, John wrote:
>
> > **
> >
> >
> > Hi all,
> >
> > I was just wondering if I have a unit running on a battery how I can swap
> > the supply voltage with the VBUS when the MSP430F5529 is connected to PC
> > through the USB interface? I know to connect the battery and the VBUS
> > together through diodes. There is a disadvantage this way which drops the
> > battery voltage by 0.4V. Any suggestion would be appreciated.
> >
> > Thanks,
> >
> > John.
> >
> >
> > --
> Lu Filipe Rossi
> Electrical Engineer
> Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> Escola Politnica
> Universidade de S Paulo
> Cel. +55 (11) 7662-9234
>
>
>
Reply by ●January 7, 20132013-01-07
Hello, John!
Are you using
MSP430F5529 USB Experimenters Board?
If so, please check this link (
http://www.ti.com/lit/ug/slau330a/slau330a.pdf) on pg 18. You can find
jumper settings when powering from battery or from usb.
Regards!
Fero Santos
On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
a...@gmail.com> wrote:
> **
> Isn't it necessary to control the mosfet gate? I guess it is not that
> simple as to replace a diode by a mosfet.
>
> 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > Use a P Channel MOSFET.
> >
> > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> >
> > > **
> > >
> > >
> > > Hi all,
> > >
> > > I was just wondering if I have a unit running on a battery how I can
> swap
> > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> PC
> > > through the USB interface? I know to connect the battery and the VBUS
> > > together through diodes. There is a disadvantage this way which drops
> the
> > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > >
> > > Thanks,
> > >
> > > John.
> > >
> > >
> > >
> >
> >
> >
> > --
> > Lu Filipe Rossi
> > Electrical Engineer
> > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > Escola Politnica
> > Universidade de S Paulo
> > Cel. +55 (11) 7662-9234
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
Are you using
MSP430F5529 USB Experimenters Board?
If so, please check this link (
http://www.ti.com/lit/ug/slau330a/slau330a.pdf) on pg 18. You can find
jumper settings when powering from battery or from usb.
Regards!
Fero Santos
On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
a...@gmail.com> wrote:
> **
> Isn't it necessary to control the mosfet gate? I guess it is not that
> simple as to replace a diode by a mosfet.
>
> 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > Use a P Channel MOSFET.
> >
> > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> >
> > > **
> > >
> > >
> > > Hi all,
> > >
> > > I was just wondering if I have a unit running on a battery how I can
> swap
> > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> PC
> > > through the USB interface? I know to connect the battery and the VBUS
> > > together through diodes. There is a disadvantage this way which drops
> the
> > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > >
> > > Thanks,
> > >
> > > John.
> > >
> > >
> > >
> >
> >
> >
> > --
> > Lu Filipe Rossi
> > Electrical Engineer
> > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > Escola Politnica
> > Universidade de S Paulo
> > Cel. +55 (11) 7662-9234
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
Reply by ●January 7, 20132013-01-07
It is infact very simple. The mosfet gate is controlled by the external
voltage.
Take a look:
[image: Inline image 2]
Where VAUX is VBUS.
So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
(considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
when the USB is connected it will block MOSFET conduction and supply VOUT.
When VAUX is floating the gate will be pulled to ground and turn the MOSFET
On.
You just need a low Ron Mosfet but that is simple to find.
Regards,
On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
a...@gmail.com> wrote:
> **
> Isn't it necessary to control the mosfet gate? I guess it is not that
> simple as to replace a diode by a mosfet.
>
> 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > Use a P Channel MOSFET.
> >
> > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Hi all,
> > >
> > > I was just wondering if I have a unit running on a battery how I can
> swap
> > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> PC
> > > through the USB interface? I know to connect the battery and the VBUS
> > > together through diodes. There is a disadvantage this way which drops
> the
> > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > >
> > > Thanks,
> > >
> > > John.
> > >
> > >
> > >
> >
> >
> >
> > --
> > Lu Filipe Rossi
> > Electrical Engineer
> > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > Escola Politnica
> > Universidade de S Paulo
> > Cel. +55 (11) 7662-9234
> >
> >
> >
> >
> >
> >
> >
>
> >
> >
> >
> >
voltage.
Take a look:
[image: Inline image 2]
Where VAUX is VBUS.
So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
(considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
when the USB is connected it will block MOSFET conduction and supply VOUT.
When VAUX is floating the gate will be pulled to ground and turn the MOSFET
On.
You just need a low Ron Mosfet but that is simple to find.
Regards,
On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
a...@gmail.com> wrote:
> **
> Isn't it necessary to control the mosfet gate? I guess it is not that
> simple as to replace a diode by a mosfet.
>
> 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > Use a P Channel MOSFET.
> >
> > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Hi all,
> > >
> > > I was just wondering if I have a unit running on a battery how I can
> swap
> > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> PC
> > > through the USB interface? I know to connect the battery and the VBUS
> > > together through diodes. There is a disadvantage this way which drops
> the
> > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > >
> > > Thanks,
> > >
> > > John.
> > >
> > >
> > >
> >
> >
> >
> > --
> > Lu Filipe Rossi
> > Electrical Engineer
> > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > Escola Politnica
> > Universidade de S Paulo
> > Cel. +55 (11) 7662-9234
> >
> >
> >
> >
> >
> >
> >
>
> >
> >
> >
> >
Reply by ●January 7, 20132013-01-07
Luis, thanks for the information. But I cannot see your image, would you
mind uploading it to a host, for example http://www.imgur.com
Thanks,
Kyle
On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi wrote:
> It is infact very simple. The mosfet gate is controlled by the external
> voltage.
>
> Take a look:
>
> [image: Inline image 2]
> Where VAUX is VBUS.
>
> So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> when the USB is connected it will block MOSFET conduction and supply VOUT.
> When VAUX is floating the gate will be pulled to ground and turn the MOSFET
> On.
>
> You just need a low Ron Mosfet but that is simple to find.
>
> Regards,
>
> On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> a...@gmail.com> wrote:
>
> > **
> >
> >
> > Isn't it necessary to control the mosfet gate? I guess it is not that
> > simple as to replace a diode by a mosfet.
> >
> > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> >
> >
> > > Use a P Channel MOSFET.
> > >
> > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Hi all,
> > > >
> > > > I was just wondering if I have a unit running on a battery how I can
> > swap
> > > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> > PC
> > > > through the USB interface? I know to connect the battery and the VBUS
> > > > together through diodes. There is a disadvantage this way which drops
> > the
> > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > >
> > > > Thanks,
> > > >
> > > > John.
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > > --
> > > Lu Filipe Rossi
> > > Electrical Engineer
> > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > Escola Politnica
> > > Universidade de S Paulo
> > > Cel. +55 (11) 7662-9234
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> > >
> > >
> > >
> > >
mind uploading it to a host, for example http://www.imgur.com
Thanks,
Kyle
On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi wrote:
> It is infact very simple. The mosfet gate is controlled by the external
> voltage.
>
> Take a look:
>
> [image: Inline image 2]
> Where VAUX is VBUS.
>
> So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> when the USB is connected it will block MOSFET conduction and supply VOUT.
> When VAUX is floating the gate will be pulled to ground and turn the MOSFET
> On.
>
> You just need a low Ron Mosfet but that is simple to find.
>
> Regards,
>
> On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> a...@gmail.com> wrote:
>
> > **
> >
> >
> > Isn't it necessary to control the mosfet gate? I guess it is not that
> > simple as to replace a diode by a mosfet.
> >
> > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> >
> >
> > > Use a P Channel MOSFET.
> > >
> > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Hi all,
> > > >
> > > > I was just wondering if I have a unit running on a battery how I can
> > swap
> > > > the supply voltage with the VBUS when the MSP430F5529 is connected to
> > PC
> > > > through the USB interface? I know to connect the battery and the VBUS
> > > > together through diodes. There is a disadvantage this way which drops
> > the
> > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > >
> > > > Thanks,
> > > >
> > > > John.
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > > --
> > > Lu Filipe Rossi
> > > Electrical Engineer
> > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > Escola Politnica
> > > Universidade de S Paulo
> > > Cel. +55 (11) 7662-9234
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
> > >
> > >
> > >
> > >
Reply by ●January 7, 20132013-01-07
There you go:
http://i.imgur.com/r6bDg.png?1
Of course the VOUT must be regulated to be used with MSP430
Regards,
On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis wrote:
> **
> Luis, thanks for the information. But I cannot see your image, would you
> mind uploading it to a host, for example http://www.imgur.com
>
> Thanks,
> Kyle
>
> On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> >wrote:
> > It is infact very simple. The mosfet gate is controlled by the external
> > voltage.
> >
> > Take a look:
> >
> > [image: Inline image 2]
> > Where VAUX is VBUS.
> >
> > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> > when the USB is connected it will block MOSFET conduction and supply
> VOUT.
> > When VAUX is floating the gate will be pulled to ground and turn the
> MOSFET
> > On.
> >
> > You just need a low Ron Mosfet but that is simple to find.
> >
> > Regards,
> >
> > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > a...@gmail.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > simple as to replace a diode by a mosfet.
> > >
> > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > >
> > >
> > > > Use a P Channel MOSFET.
> > > >
> > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > >
> > > > > **
> > >
> > > > >
> > > > >
> > > > > Hi all,
> > > > >
> > > > > I was just wondering if I have a unit running on a battery how I
> can
> > > swap
> > > > > the supply voltage with the VBUS when the MSP430F5529 is connected
> to
> > > PC
> > > > > through the USB interface? I know to connect the battery and the
> VBUS
> > > > > together through diodes. There is a disadvantage this way which
> drops
> > > the
> > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > John.
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Lu Filipe Rossi
> > > > Electrical Engineer
> > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > Escola Politnica
> > > > Universidade de S Paulo
> > > > Cel. +55 (11) 7662-9234
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > >
> > > >
> > > >
> > > >
http://i.imgur.com/r6bDg.png?1
Of course the VOUT must be regulated to be used with MSP430
Regards,
On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis wrote:
> **
> Luis, thanks for the information. But I cannot see your image, would you
> mind uploading it to a host, for example http://www.imgur.com
>
> Thanks,
> Kyle
>
> On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> >wrote:
> > It is infact very simple. The mosfet gate is controlled by the external
> > voltage.
> >
> > Take a look:
> >
> > [image: Inline image 2]
> > Where VAUX is VBUS.
> >
> > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> > when the USB is connected it will block MOSFET conduction and supply
> VOUT.
> > When VAUX is floating the gate will be pulled to ground and turn the
> MOSFET
> > On.
> >
> > You just need a low Ron Mosfet but that is simple to find.
> >
> > Regards,
> >
> > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > a...@gmail.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > simple as to replace a diode by a mosfet.
> > >
> > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > >
> > >
> > > > Use a P Channel MOSFET.
> > > >
> > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > >
> > > > > **
> > >
> > > > >
> > > > >
> > > > > Hi all,
> > > > >
> > > > > I was just wondering if I have a unit running on a battery how I
> can
> > > swap
> > > > > the supply voltage with the VBUS when the MSP430F5529 is connected
> to
> > > PC
> > > > > through the USB interface? I know to connect the battery and the
> VBUS
> > > > > together through diodes. There is a disadvantage this way which
> drops
> > > the
> > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > John.
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Lu Filipe Rossi
> > > > Electrical Engineer
> > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > Escola Politnica
> > > > Universidade de S Paulo
> > > > Cel. +55 (11) 7662-9234
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > >
> > > >
> > > >
> > > >
Reply by ●January 9, 20132013-01-09
Hello all,
Thank you for your reply. I like your circuit Luisf a lot. It works but I am not sure why. Does it have to due to the threshold?
One further question in MSP430F5529 does DVCC and AVCC pins are internally connected or we have to connect them externally?
High Regards,
John.
________________________________
From: Luis Filipe Rossi
To: m...
Sent: Monday, January 7, 2013 7:35 AM
Subject: Re: [msp430] VBUS on MSP430F5529
There you go:
http://i.imgur.com/r6bDg.png?1
Of course the VOUT must be regulated to be used with MSP430
Regards,
On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis wrote:
> **
> Luis, thanks for the information. But I cannot see your image, would you
> mind uploading it to a host, for example http://www.imgur.com
>
> Thanks,
> Kyle
>
> On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> >wrote:
> > It is infact very simple. The mosfet gate is controlled by the external
> > voltage.
> >
> > Take a look:
> >
> > [image: Inline image 2]
> > Where VAUX is VBUS.
> >
> > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> > when the USB is connected it will block MOSFET conduction and supply
> VOUT.
> > When VAUX is floating the gate will be pulled to ground and turn the
> MOSFET
> > On.
> >
> > You just need a low Ron Mosfet but that is simple to find.
> >
> > Regards,
> >
> > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > a...@gmail.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > simple as to replace a diode by a mosfet.
> > >
> > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > >
> > >
> > > > Use a P Channel MOSFET.
> > > >
> > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > >
> > > > > **
> > >
> > > > >
> > > > >
> > > > > Hi all,
> > > > >
> > > > > I was just wondering if I have a unit running on a battery how I
> can
> > > swap
> > > > > the supply voltage with the VBUS when the MSP430F5529 is connected
> to
> > > PC
> > > > > through the USB interface? I know to connect the battery and the
> VBUS
> > > > > together through diodes. There is a disadvantage this way which
> drops
> > > the
> > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > John.
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Lu Filipe Rossi
> > > > Electrical Engineer
> > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > Escola Politnica
> > > > Universidade de S Paulo
> > > > Cel. +55 (11) 7662-9234
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > >
> > > >
> > > >
> > > >
Thank you for your reply. I like your circuit Luisf a lot. It works but I am not sure why. Does it have to due to the threshold?
One further question in MSP430F5529 does DVCC and AVCC pins are internally connected or we have to connect them externally?
High Regards,
John.
________________________________
From: Luis Filipe Rossi
To: m...
Sent: Monday, January 7, 2013 7:35 AM
Subject: Re: [msp430] VBUS on MSP430F5529
There you go:
http://i.imgur.com/r6bDg.png?1
Of course the VOUT must be regulated to be used with MSP430
Regards,
On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis wrote:
> **
> Luis, thanks for the information. But I cannot see your image, would you
> mind uploading it to a host, for example http://www.imgur.com
>
> Thanks,
> Kyle
>
> On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> >wrote:
> > It is infact very simple. The mosfet gate is controlled by the external
> > voltage.
> >
> > Take a look:
> >
> > [image: Inline image 2]
> > Where VAUX is VBUS.
> >
> > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > (considering a standard LiPo or LiIon Battery with 4.2V charged voltage)
> > when the USB is connected it will block MOSFET conduction and supply
> VOUT.
> > When VAUX is floating the gate will be pulled to ground and turn the
> MOSFET
> > On.
> >
> > You just need a low Ron Mosfet but that is simple to find.
> >
> > Regards,
> >
> > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > a...@gmail.com> wrote:
> >
> > > **
>
> > >
> > >
> > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > simple as to replace a diode by a mosfet.
> > >
> > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > >
> > >
> > > > Use a P Channel MOSFET.
> > > >
> > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > >
> > > > > **
> > >
> > > > >
> > > > >
> > > > > Hi all,
> > > > >
> > > > > I was just wondering if I have a unit running on a battery how I
> can
> > > swap
> > > > > the supply voltage with the VBUS when the MSP430F5529 is connected
> to
> > > PC
> > > > > through the USB interface? I know to connect the battery and the
> VBUS
> > > > > together through diodes. There is a disadvantage this way which
> drops
> > > the
> > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > John.
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Lu Filipe Rossi
> > > > Electrical Engineer
> > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > Escola Politnica
> > > > Universidade de S Paulo
> > > > Cel. +55 (11) 7662-9234
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > > >
> > > >
> > > >
> > > >
Reply by ●January 9, 20132013-01-09
Hi John,
I am not 100% sure if you need that but you can check the example
circuit boards put out by TI. One thing I always do if I am learning a
new processor family is to get, the Data sheet for your the specific
chip, the family user guide of your chip , and the schematic of the
experimenter board for your chip. If you want to make programming and
designing circuits easier for yourself spend the time to at least skim
those documents and always have them in hand, because they will help.
Jake G.
On 1/8/2013 10:10 PM, john Mcdonald wrote:
>
> Hello all,
>
> Thank you for your reply. I like your circuit Luisf a lot. It works
> but I am not sure why. Does it have to due to the threshold?
> One further question in MSP430F5529 does DVCC and AVCC pins are
> internally connected or we have to connect them externally?
>
> High Regards,
>
> John.
>
> ________________________________
> From: Luis Filipe Rossi l...@gmail.com
> >
> To: m...
> Sent: Monday, January 7, 2013 7:35 AM
> Subject: Re: [msp430] VBUS on MSP430F5529
>
> There you go:
>
> http://i.imgur.com/r6bDg.png?1
>
> Of course the VOUT must be regulated to be used with MSP430
>
> Regards,
>
> On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis k...@gmail.com
> > wrote:
>
> > **
> >
> >
> > Luis, thanks for the information. But I cannot see your image, would you
> > mind uploading it to a host, for example http://www.imgur.com
> >
> > Thanks,
> > Kyle
> >
> > On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi
> l...@gmail.com
> > >wrote:
> >
> >
> > > It is infact very simple. The mosfet gate is controlled by the
> external
> > > voltage.
> > >
> > > Take a look:
> > >
> > > [image: Inline image 2]
> > > Where VAUX is VBUS.
> > >
> > > So if VBUS is present and VBAT is always lower than VBUS - the
> Diode Vf
> > > (considering a standard LiPo or LiIon Battery with 4.2V charged
> voltage)
> > > when the USB is connected it will block MOSFET conduction and supply
> > VOUT.
> > > When VAUX is floating the gate will be pulled to ground and turn the
> > MOSFET
> > > On.
> > >
> > > You just need a low Ron Mosfet but that is simple to find.
> > >
> > > Regards,
> > >
> > > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > > a...@gmail.com
> > wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Isn't it necessary to control the mosfet gate? I guess it is not
> that
> > > > simple as to replace a diode by a mosfet.
> > > >
> > > > 2013/1/7 Luis Filipe Rossi l...@gmail.com
> >
> > > >
> > > >
> > > > > Use a P Channel MOSFET.
> > > > >
> > > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com
> > wrote:
> > > > >
> > > > > > **
> > > >
> > > > > >
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I was just wondering if I have a unit running on a battery how I
> > can
> > > > swap
> > > > > > the supply voltage with the VBUS when the MSP430F5529 is
> connected
> > to
> > > > PC
> > > > > > through the USB interface? I know to connect the battery and the
> > VBUS
> > > > > > together through diodes. There is a disadvantage this way which
> > drops
> > > > the
> > > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > John.
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Lu Filipe Rossi
> > > > > Electrical Engineer
> > > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > > Escola Politnica
> > > > > Universidade de S Paulo
> > > > > Cel. +55 (11) 7662-9234
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > >
> > > > >
>
> > > > >
> > > > >
I am not 100% sure if you need that but you can check the example
circuit boards put out by TI. One thing I always do if I am learning a
new processor family is to get, the Data sheet for your the specific
chip, the family user guide of your chip , and the schematic of the
experimenter board for your chip. If you want to make programming and
designing circuits easier for yourself spend the time to at least skim
those documents and always have them in hand, because they will help.
Jake G.
On 1/8/2013 10:10 PM, john Mcdonald wrote:
>
> Hello all,
>
> Thank you for your reply. I like your circuit Luisf a lot. It works
> but I am not sure why. Does it have to due to the threshold?
> One further question in MSP430F5529 does DVCC and AVCC pins are
> internally connected or we have to connect them externally?
>
> High Regards,
>
> John.
>
> ________________________________
> From: Luis Filipe Rossi l...@gmail.com
> >
> To: m...
> Sent: Monday, January 7, 2013 7:35 AM
> Subject: Re: [msp430] VBUS on MSP430F5529
>
> There you go:
>
> http://i.imgur.com/r6bDg.png?1
>
> Of course the VOUT must be regulated to be used with MSP430
>
> Regards,
>
> On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis k...@gmail.com
> > wrote:
>
> > **
> >
> >
> > Luis, thanks for the information. But I cannot see your image, would you
> > mind uploading it to a host, for example http://www.imgur.com
> >
> > Thanks,
> > Kyle
> >
> > On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi
> l...@gmail.com
> > >wrote:
> >
> >
> > > It is infact very simple. The mosfet gate is controlled by the
> external
> > > voltage.
> > >
> > > Take a look:
> > >
> > > [image: Inline image 2]
> > > Where VAUX is VBUS.
> > >
> > > So if VBUS is present and VBAT is always lower than VBUS - the
> Diode Vf
> > > (considering a standard LiPo or LiIon Battery with 4.2V charged
> voltage)
> > > when the USB is connected it will block MOSFET conduction and supply
> > VOUT.
> > > When VAUX is floating the gate will be pulled to ground and turn the
> > MOSFET
> > > On.
> > >
> > > You just need a low Ron Mosfet but that is simple to find.
> > >
> > > Regards,
> > >
> > > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > > a...@gmail.com
> > wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Isn't it necessary to control the mosfet gate? I guess it is not
> that
> > > > simple as to replace a diode by a mosfet.
> > > >
> > > > 2013/1/7 Luis Filipe Rossi l...@gmail.com
> >
> > > >
> > > >
> > > > > Use a P Channel MOSFET.
> > > > >
> > > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com
> > wrote:
> > > > >
> > > > > > **
> > > >
> > > > > >
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I was just wondering if I have a unit running on a battery how I
> > can
> > > > swap
> > > > > > the supply voltage with the VBUS when the MSP430F5529 is
> connected
> > to
> > > > PC
> > > > > > through the USB interface? I know to connect the battery and the
> > VBUS
> > > > > > together through diodes. There is a disadvantage this way which
> > drops
> > > > the
> > > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > John.
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Lu Filipe Rossi
> > > > > Electrical Engineer
> > > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > > Escola Politnica
> > > > > Universidade de S Paulo
> > > > > Cel. +55 (11) 7662-9234
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > >
> > > > >
>
> > > > >
> > > > >
Reply by ●January 9, 20132013-01-09
Hello John,
The circuit works as follows. Considering a VBUS of 5V and a VBAT of 3.7V.
When USB is connected the volltage at MOSFET GATE will be 5V and the
voltage at Mosfet Source will be 5V - VF. In this scenario you got a
positive VGS and the mosfet is blocked. Also the mosfet body diode is
reverse polarized so it is not conducting. When USB is not connecting the
MOSFET GATE is pulled to ground. Also in a initial solution the Voltage at
MOSFET Source is something close to 0V. In such situation the mosfet would
be also blocked. However the body diode will start to conduct creating a
negative VGS value and turning ON the mosfet.
Let me know if i was enough clear.
Regarding DVCC and AVCC, yes you must connect then externally. If you
really need a clean AD measurement you should also filter your VCC with a
ferrite bead before connecting to AVCC.
Regards,
On Wed, Jan 9, 2013 at 4:10 AM, john Mcdonald wrote:
> **
> Hello all,
>
> Thank you for your reply. I like your circuit Luisf a lot. It works but
> I am not sure why. Does it have to due to the threshold?
> One further question in MSP430F5529 does DVCC and AVCC pins are internally
> connected or we have to connect them externally?
>
> High Regards,
>
> John.
>
> ________________________________
> From: Luis Filipe Rossi l...@gmail.com>
> To: m...
> Sent: Monday, January 7, 2013 7:35 AM
> Subject: Re: [msp430] VBUS on MSP430F5529
> There you go:
>
> http://i.imgur.com/r6bDg.png?1
>
> Of course the VOUT must be regulated to be used with MSP430
>
> Regards,
>
> On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis k...@gmail.com> wrote:
>
> > **
>
> >
> >
> > Luis, thanks for the information. But I cannot see your image, would you
> > mind uploading it to a host, for example http://www.imgur.com
> >
> > Thanks,
> > Kyle
> >
> > On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> > >wrote:
> >
> >
> > > It is infact very simple. The mosfet gate is controlled by the external
> > > voltage.
> > >
> > > Take a look:
> > >
> > > [image: Inline image 2]
> > > Where VAUX is VBUS.
> > >
> > > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > > (considering a standard LiPo or LiIon Battery with 4.2V charged
> voltage)
> > > when the USB is connected it will block MOSFET conduction and supply
> > VOUT.
> > > When VAUX is floating the gate will be pulled to ground and turn the
> > MOSFET
> > > On.
> > >
> > > You just need a low Ron Mosfet but that is simple to find.
> > >
> > > Regards,
> > >
> > > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > > a...@gmail.com> wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > > simple as to replace a diode by a mosfet.
> > > >
> > > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > > >
> > > >
> > > > > Use a P Channel MOSFET.
> > > > >
> > > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > > >
> > > > > > **
> > > >
> > > > > >
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I was just wondering if I have a unit running on a battery how I
> > can
> > > > swap
> > > > > > the supply voltage with the VBUS when the MSP430F5529 is
> connected
> > to
> > > > PC
> > > > > > through the USB interface? I know to connect the battery and the
> > VBUS
> > > > > > together through diodes. There is a disadvantage this way which
> > drops
> > > > the
> > > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > John.
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Lu Filipe Rossi
> > > > > Electrical Engineer
> > > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > > Escola Politnica
> > > > > Universidade de S Paulo
> > > > > Cel. +55 (11) 7662-9234
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > >
> > > > >
> > > > >
> > > > >
The circuit works as follows. Considering a VBUS of 5V and a VBAT of 3.7V.
When USB is connected the volltage at MOSFET GATE will be 5V and the
voltage at Mosfet Source will be 5V - VF. In this scenario you got a
positive VGS and the mosfet is blocked. Also the mosfet body diode is
reverse polarized so it is not conducting. When USB is not connecting the
MOSFET GATE is pulled to ground. Also in a initial solution the Voltage at
MOSFET Source is something close to 0V. In such situation the mosfet would
be also blocked. However the body diode will start to conduct creating a
negative VGS value and turning ON the mosfet.
Let me know if i was enough clear.
Regarding DVCC and AVCC, yes you must connect then externally. If you
really need a clean AD measurement you should also filter your VCC with a
ferrite bead before connecting to AVCC.
Regards,
On Wed, Jan 9, 2013 at 4:10 AM, john Mcdonald wrote:
> **
> Hello all,
>
> Thank you for your reply. I like your circuit Luisf a lot. It works but
> I am not sure why. Does it have to due to the threshold?
> One further question in MSP430F5529 does DVCC and AVCC pins are internally
> connected or we have to connect them externally?
>
> High Regards,
>
> John.
>
> ________________________________
> From: Luis Filipe Rossi l...@gmail.com>
> To: m...
> Sent: Monday, January 7, 2013 7:35 AM
> Subject: Re: [msp430] VBUS on MSP430F5529
> There you go:
>
> http://i.imgur.com/r6bDg.png?1
>
> Of course the VOUT must be regulated to be used with MSP430
>
> Regards,
>
> On Mon, Jan 7, 2013 at 1:29 PM, Kyle Lewis k...@gmail.com> wrote:
>
> > **
>
> >
> >
> > Luis, thanks for the information. But I cannot see your image, would you
> > mind uploading it to a host, for example http://www.imgur.com
> >
> > Thanks,
> > Kyle
> >
> > On Mon, Jan 7, 2013 at 7:11 AM, Luis Filipe Rossi l...@gmail.com
> > >wrote:
> >
> >
> > > It is infact very simple. The mosfet gate is controlled by the external
> > > voltage.
> > >
> > > Take a look:
> > >
> > > [image: Inline image 2]
> > > Where VAUX is VBUS.
> > >
> > > So if VBUS is present and VBAT is always lower than VBUS - the Diode Vf
> > > (considering a standard LiPo or LiIon Battery with 4.2V charged
> voltage)
> > > when the USB is connected it will block MOSFET conduction and supply
> > VOUT.
> > > When VAUX is floating the gate will be pulled to ground and turn the
> > MOSFET
> > > On.
> > >
> > > You just need a low Ron Mosfet but that is simple to find.
> > >
> > > Regards,
> > >
> > > On Mon, Jan 7, 2013 at 9:37 AM, Adeilton Oliveira <
> > > a...@gmail.com> wrote:
> > >
> > > > **
> >
> > > >
> > > >
> > > > Isn't it necessary to control the mosfet gate? I guess it is not that
> > > > simple as to replace a diode by a mosfet.
> > > >
> > > > 2013/1/7 Luis Filipe Rossi l...@gmail.com>
> > > >
> > > >
> > > > > Use a P Channel MOSFET.
> > > > >
> > > > > On Mon, Jan 7, 2013 at 2:27 AM, John e...@yahoo.com> wrote:
> > > > >
> > > > > > **
> > > >
> > > > > >
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I was just wondering if I have a unit running on a battery how I
> > can
> > > > swap
> > > > > > the supply voltage with the VBUS when the MSP430F5529 is
> connected
> > to
> > > > PC
> > > > > > through the USB interface? I know to connect the battery and the
> > VBUS
> > > > > > together through diodes. There is a disadvantage this way which
> > drops
> > > > the
> > > > > > battery voltage by 0.4V. Any suggestion would be appreciated.
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > > John.
> > > > > >
> > > > > >
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Lu Filipe Rossi
> > > > > Electrical Engineer
> > > > > Biomechatronics Lab. / Grupo de Sensores Integreis e Sistemas
> > > > > Escola Politnica
> > > > > Universidade de S Paulo
> > > > > Cel. +55 (11) 7662-9234
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > > >
> > > > >
> > > > >
> > > > >
