Hi I do not want to provide more than one connector t the user. John
PSoC or FPGA?
Started by ●March 20, 2011
Reply by ●March 21, 20112011-03-21
Reply by ●March 21, 20112011-03-21
On 21/03/2011 20:44, john1987 wrote:> Hi, > > I need to connect a 12 volts DC lead acid battery to a circuit. The > circuit draws 100mA and works at 3.3V. I am planning to use 7805 to > drop the voltage from 12 to 5 volts.Wouldn't the 7803SR be worth considering for this job? Better efficiency from a switcher would extend battery life.> > The first thing is that how can I bypass the 7805 while charging the > battery? > > The thing is that I also needs to recharge the battery too. The > Circuit and the battery charger both have same input power connector > on them and the battery has the mating connector for both of them.Unclear from your description whether you mean here that the charger could be accidentally plugged into the thing requiring 3.3v regulated. If so that sounds like a recipe for disaster. Ditto if you mean that the 3.3v output is capable of accepting the chargers plug. No reason why the voltage regulator and its load has to be disconnected when the battery is on charge. Regulators will stand 15v (or even 30v). Regards, Martin Brown
Reply by ●March 21, 20112011-03-21
Phil Hobbs wrote:> john1987 wrote: >> Hi, >> >> I need to connect a 12 volts DC lead acid battery to a circuit. The >> circuit draws 100mA and works at 3.3V. I am planning to use 7805 to >> drop the voltage from 12 to 5 volts. >> >> The first thing is that how can I bypass the 7805 while charging the >> battery? >> >> The thing is that I also needs to recharge the battery too. The >> Circuit and the battery charger both have same input power connector >> on them and the battery has the mating connector for both of them. >> >> >> >> Thanks >> John, > > Um, how about putting another connector on the input side of the 7805? > > Cheers > > Phil Hobbs >So you want to put a >12V supply on the output of the 7805 to charge the battery? If your circuitry can stand 12V, why not just delete the 7805 and be done? Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal ElectroOptical Innovations 55 Orchard Rd Briarcliff Manor NY 10510 845-480-2058 email: hobbs (atsign) electrooptical (period) net http://electrooptical.net
Reply by ●March 21, 20112011-03-21
"john1987" <conphiloso@hotmail.com> wrote in message news:015f04a6-fe16-484e-8706-25270ca29a08@a21g2000prj.googlegroups.com...> Hi > I do not want to provide more than one connector t the user. > > JohnOkay, So use a three contact connector...one and a common for powering your device and a second and common for charging your battery. Same connector, different pins. --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
Reply by ●March 21, 20112011-03-21
The battery has a connector A on it. The circuit and the battery charger has connector B on them. Connector A is a mate of connector B. The battery is 12 volts goes into 7805 the out put of the 7805( connector A) goes into the circuit that has the voltage regulator that outputs 3.3 volts. Now , I want the user to plug in the battery into the circuit and when battery gets dischagred he / she can plug the batter into its charger. but 7805 is there now in the middle of the battery and the battery charger. So, how to solve this problem. Thanks John
Reply by ●March 21, 20112011-03-21
On Mon, 21 Mar 2011 14:47:49 -0700 (PDT), john1987 <conphiloso@hotmail.com> wrote:>The battery has a connector A on it. The circuit and the battery >charger has connector B on them. Connector A is a mate of connector B. >The battery is 12 volts goes into 7805 the out put of the >7805( connector A) goes into the circuit that has the voltage >regulator that outputs 3.3 volts. > >Now , I want the user to plug in the battery into the circuit and when >battery gets dischagred he / she can plug the batter into its charger. >but 7805 is there now in the middle of the battery and the battery >charger. So, how to solve this problem. > >Thanks >JohnThoroughly confusing. As Confucius say, picture worth thousand words :-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | Remember: Once you go over the hill, you pick up speed
Reply by ●March 21, 20112011-03-21
On 21/03/2011 21:47, john1987 wrote:> The battery has a connector A on it. The circuit and the battery > charger has connector B on them. Connector A is a mate of connector B. > The battery is 12 volts goes into 7805 the out put of the > 7805( connector A) goes into the circuit that has the voltage > regulator that outputs 3.3 volts. > > Now , I want the user to plug in the battery into the circuit and when > battery gets dischagred he / she can plug the batter into its charger. > but 7805 is there now in the middle of the battery and the battery > charger. So, how to solve this problem.Since you have volts to spare in both directions how about a diode in series with the regulator output and a diode reverse polarity across the regulator. VA < 5v the series diode passes current to the load and VA >12v the parallel diode passes current from the charger to the battery. The odd resistor may be needed to prevent instability and avoid sharp current surges when the charger is first plugged in. That is if I have understood what you want to do. Regards, Martin Brown
Reply by ●March 21, 20112011-03-21
On Mon, 21 Mar 2011 08:41:39 GMT, Jan Panteltje <pNaonStpealmtje@yahoo.com> wrote:>On a sunny day (Sun, 20 Mar 2011 15:16:14 -0500) it happened >"krw@att.bizzzzzzzzzzzz" <krw@att.bizzzzzzzzzzzz> wrote in ><62oco610kr2ullbgc3al8rcc0iq1gek6r0@4ax.com>: > >>On Sun, 20 Mar 2011 18:14:25 GMT, Jan Panteltje <pNaonStpealmtje@yahoo.com> >>wrote: >> >> >>> >>>There is too much simulations in this world. >> >>You needn't say anything else. At least you're consistent; clueless. > >Take your intelligence for example. > >I do not think we will ever see any code from you,Wow! You got that right. I don't WRITE CODE, moron.>all you do is boast about how big the things are you make, >insult people, etc, >while from the time it takes you to do the simplest things I guess you are at least incompetent, and at most a windbag.You sure are a useless twit, JP.
Reply by ●March 21, 20112011-03-21
On Mon, 21 Mar 2011 15:44:26 GMT, nico@puntnl.niks (Nico Coesel) wrote:>Muzaffer Kal <kal@dspia.com> wrote: > >>On Sun, 20 Mar 2011 22:45:45 GMT, nico@puntnl.niks (Nico Coesel) >>wrote: >>... >>>You can simulate a lot but creating a set of tests which covers all >>>the possible mayhem coming from the outside world is next to >>>impossible. >> >>This suggests that making an ASIC work right the first time is next to >>impossible but experience shows that it's not. So it's just a matter >>of how diligent one is with one's tests. > >Well, tell that to the big semi manufacturers :-)Um, I worked for one. I was on the verification team (a department of twelve) for some rather "big" processors.>Many >microcontrollers and SoCs have several versions with bugs. Recently >even Intel got bitten badly.Are you saying that you think simulation should make perfection automatic? No, there are too many things that go unsimulated. That is, too little simulation, not too much.>And there still may be unexpected behaviour coming from the outside >which might not be addressed by the design (incomplete specification). >If you have an ASIC you most probably need to fix the outside world, >if you are using an FPGA (or something else which is programmable) you >most likely end up fixing the FPGA design.Duh!>I think FPGA simulation is very usefull but I always got by without it >or used other methods for verification. The maximum size of the >designs I worked on is about 800k to 1M equivalent gates.How many flops? "Equivalent gates" is a meaningless number.
Reply by ●March 21, 20112011-03-21
On Sun, 20 Mar 2011 17:31:29 -0700 (PDT), hrh1818 <hrhan@att.net> wrote:>On Mar 20, 4:10�am, fasf <silusilus...@gmail.com> wrote: >> Hi, >> i've worked wit 8bit/32bit microcontrollers for 5 years and now i want >> to explore new fields, so i'm interested in these two solutions: PSoC >> and FPGA. I'm totally new (i don't know neither VHDL nor Verilog) and >> i don't understand the differences between these programmable devices. >> For hobby, what do you think is more useful to study? Can you suggest >> a low cost DevKit? >> Any getting started suggestion will be very appreciated > >You don't need to make a choice between PSOC and FPGA. Actel sells >Smartfusion. SmartFusion intelligent mixed signal FPGAs are the only >devices that integrate an FPGA, ARM� Cortex�-M3, and programmable >analog, offering full customization, For an overview see: >http://www.actel.com/products/SmartFusion/default.aspxSmartFusion is an FPGA. It's really nothing like a PSoC.>An evaluation kit is available for $99.00. See: >http://www.actel.com/products/hardware/devkits_boards/smartfusion_eval.aspxSmartFusion is really slick, but I wouldn't recommend it for an introduction into FPGAs. If he's looking to get into the business, I'd suggest something more mainstream than Actel. Too many HR types will look for Altera or Xilinx keywords (work them into the resume somehow ;-).
