Post by thread:[EE] (Fwd) [Keelynet] DIY supercapacitor as a 9VDC

------- Forwarded message follows ------- Subject: [Keelynet] DIY supercapacitor as a 9VDC battery & more Date sent: Wed, 07 Dec 2005 06:27:58 -0600 Check out this way cool 9vdc battery modification that uses a 10 FARAD capacitor....lasts up to 3 hours and recharges in 20 seconds. 12/07/05 - Supercap 9VDC Battery http://www.bairesrobotics.com.ar/elektor/10-2003%20SuperCap%20Battery.pdf 9V batteries are often found in devices that aren t used very often. If you use a NiCd rechargeable battery you may find it completely discharged by the time you need it. Capacitors on the other hand can maintain their charge for years. This circuit uses a 10F cap with a switching voltage regulator to increase the voltage from 2.3V to 9V. With a light load the cap will last up to 3 hours and once discharged it can be recharged in less than 20 seconds. Warning: PDF link. ------- End of forwarded message -------

{Quote hidden}>-----Original Message----- >From: spam_OUTpiclist-bouncesTakeThisOuTmit.edu [.....piclist-bouncesKILLspam@spam@mit.edu] >Sent: 07 December 2005 16:15 >To: piclistKILLspammit.edu >Subject: [EE] (Fwd) [Keelynet] DIY supercapacitor as a 9VDC >battery & more > > > >------- Forwarded message follows ------- > >Subject: [Keelynet] DIY supercapacitor as a 9VDC >battery & more >Date sent: Wed, 07 Dec 2005 06:27:58 -0600 > >Check out this way cool 9vdc battery modification that uses a 10 FARAD >capacitor....lasts up to 3 hours and recharges in 20 seconds. > >12/07/05 - Supercap 9VDC Battery > >www.bairesrobotics.com.ar/elektor/10-2003%20SuperCap%20B attery.pdf >9V batteries are often found in devices that aren t used very often. If >you use a NiCd rechargeable battery you may find it completely >discharged by the time you need it. >Capacitors on the other hand can maintain their charge for years. A rather bogus claim in relation to supercaps. The leakage current of the part used in that project is 1.2mA at 25 degrees C, which is not going to let it hold it's charge for more than a day or so, let alone years. The basic discrete switcher is also pretty poor with a quiescent of 2mA, it should be possible to better this by a factor of 10-20 without much difficulty. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. =======================================================================

{Quote hidden}>-----Original Message----- >From: piclist-bouncesspam_OUTmit.edu [@spam@piclist-bouncesKILLspammit.edu] >Sent: 07 December 2005 17:26 >To: Microcontroller discussion list - Public. >Subject: Re: [EE] (Fwd) [Keelynet] DIY supercapacitor as a >9VDC battery &more > > > >----- Original Message ----- >From: "Michael Rigby-Jones" <KILLspamMichael.Rigby-JonesKILLspambookham.com> >To: "Microcontroller discussion list - Public." <RemoveMEpiclistTakeThisOuTmit.edu> >Sent: Wednesday, December 07, 2005 6:03 PM >Subject: RE: [EE] (Fwd) [Keelynet] DIY supercapacitor as a >9VDC battery &more > > >| >| >| >-----Original Message----- >| >From: spamBeGonepiclist-bouncesspamBeGonemit.edu [TakeThisOuTpiclist-bouncesEraseMEspam_OUTmit.edu] >| >Sent: 07 December 2005 16:15 >| >To: RemoveMEpiclistTakeThisOuTmit.edu >| >Subject: [EE] (Fwd) [Keelynet] DIY supercapacitor as a 9VDC >battery & >| >more >| > >| > >| > >| [Description of 9V Battery replacement with 10F Cap] >| >| A rather bogus claim in relation to supercaps. The leakage >current of >| the >part used in that project is 1.2mA at 25 degrees C, which is >not going to let it hold it's charge for more than a day or >so, let alone years. >| >| The basic discrete switcher is also pretty poor with a quiescent of >| 2mA, >it should be possible to better this by a factor of 10-20 >without much difficulty. >| >| Regards >| >| Mike >| >Would be really interested in a better circuit design - would >you be please so kind and show us the better solution without >much difficulty? Thank you! Take at look at the micropower switcher design in the Art Of Electronics for a fairly discrete solution. Micropower switcher IC's are made by most of the larger semiconductor manufacturers such as Maxim, Linear Technology etc. e.g. an LT1615-1 works down to 1 volt, and consumes just 20uA when operating. It also comes in a tiny package which means you could maybe even pack two supercaps into your PP3 housing. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. =======================================================================

> Take at look at the micropower switcher design in the Art Of Electronics for a fairly discrete solution. Micropower switcher IC's are made by most of the larger semiconductor manufacturers such as Maxim, Linear Technology etc. e.g. an LT1615-1 works down to 1 volt, and consumes just 20uA when operating. It also comes in a tiny package which means you could maybe even pack two supercaps into your PP3 housing. Could anyone please post this circuit somewhere? I live in Costa Rica and it´s VERY hard for me to get some of this books... Thnkz Juan Cubillo

>> Take at look at the micropower switcher design in the Art Of >> Electronics > for a fairly discrete solution. Micropower switcher IC's are made > by most > of the larger semiconductor manufacturers such as Maxim, Linear > Technology > etc. e.g. an LT1615-1 works down to 1 volt, and consumes just 20uA > when > operating. It also comes in a tiny package which means you could > maybe even > pack two supercaps into your PP3 housing. > > Could anyone please post this circuit somewhere? I live in Costa > Rica and > it´s VERY hard for me to get some of this books... Google is (how come "EVERYONE" doesn't know this yet?) your friend. Copyright violating copies of TAOE may not be available (and may) but app notes for LT products surely are. eg Google hit #3 http://www.linear.com/pc/productDetail.do?navId=H0,C1,C1003,C1042,C1035,P1774 #2 http://www.zetex.com/3.0/a1-7.asp Datasheet with applications data galore (rebuild URL :-( ). http://linear-tech.com.cn/pc/downloadDocument.do;jsessionid=C4O6H5M2PTvOEEzzcDlXHmPb0LmR3fjRadKVgi1qs3JfOrUZzQbo!-848388738?navId=H0,C1,C1003,C1042,C1035,P1774,D3577 LT1615 is tiny - and stupidly expensive. $US1.80 in 5000 quantity. For a cheap and cheerful low cost solution with less efficiency, less cost and immense flexibility ask Google about MC34063 RM

{Quote hidden}>-----Original Message----- >From: piclist-bouncesEraseME.....mit.edu [EraseMEpiclist-bouncesmit.edu] >Sent: 08 December 2005 09:07 >To: Microcontroller discussion list - Public. >Subject: Re: [EE] (Fwd) [Keelynet] DIY supercapacitor as a >9VDC battery &more > > >>> Take at look at the micropower switcher design in the Art Of >>> Electronics >> for a fairly discrete solution. Micropower switcher IC's are made >> by most >> of the larger semiconductor manufacturers such as Maxim, Linear >> Technology >> etc. e.g. an LT1615-1 works down to 1 volt, and consumes just 20uA >> when >> operating. It also comes in a tiny package which means you could >> maybe even >> pack two supercaps into your PP3 housing. >> >> Could anyone please post this circuit somewhere? I live in Costa >> Rica and >> it´s VERY hard for me to get some of this books... > > >Google is (how come "EVERYONE" doesn't know this yet?) your friend. >Copyright violating copies of TAOE may not be available (and may) but >app notes for LT products surely are. > >eg > >Google hit #3 > >www.linear.com/pc/productDetail.do?navId=H0,C1,C1003,C10 42,C1035,P1774 {Quote hidden}>#2 http://www.zetex.com/3.0/a1-7.asp >Datasheet with applications data galore (rebuild URL :-( ). > http://linear-tech.com.cn/pc/downloadDocument.do;jsessionid=C4O6H5M2PTvOEEzzcDlXHmPb0LmR3fjRadKVgi1qs3JfOrUZzQbo!-848388738?navId=H0,C1,C1003,C1042,C1035,P1774,D3577 >LT1615 is tiny - and stupidly expensive. $US1.80 in 5000 quantity. >For a cheap and cheerful low cost solution with less efficiency, less >cost and immense flexibility ask Google about MC34063 Russell, The reason I picked the LT1615 from the numerous devices available was primarily it's ultra low quiescent current, and it's ability to work down to 1 volt. Being tiny is a positive advantage for this application. The MC34063 needs 3 volts minimum, and the datasheet lists an operating current of 4mA @5v. The supercap has a maximum working voltage of 2.3volts which makes the Motorla a non-starter for this application. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. =======================================================================