battery chargers, again
in [Design]
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From: Joerg on 30 Sep 2009 17:41 Jan Panteltje wrote: > On a sunny day (Wed, 30 Sep 2009 14:31:10 -0700) it happened Joerg > <invalid(a)invalid.invalid> wrote in <7ii112F31qi8nU3(a)mid.individual.net>: > >> Jan Panteltje wrote: >>> On a sunny day (Wed, 30 Sep 2009 13:01:31 -0700) it happened Joerg >>> <invalid(a)invalid.invalid> wrote in <7ihrovF320ev9U2(a)mid.individual.net>: >>> >>>>> All depends, 10mV is fine with me:-) >>>>> >>>>> You really got to come up with some numbers, else it all makes no sense, >>>>> >>>> Ok, this is the number I typically need: Not being able to show the >>>> ripple on a scope when set to 2mV/div. Good enough? >>>> >>>> Seriously, 10mV piping out would be disastrous when doing things like >>>> ultrasound experiments. >>> LOL I have done quite interesting ultrasound Doppler experimensts. >>> If your circuit is so bad that it cannot tolerate 10 mV ripple on the supply line, >>> then I suggest you change to gardening. >>> >> So, then, how many beamformers, audio Dopplers and color flow modules >> have you brought from blank sheet to market? Experiments, revenue >> product, two different things. > > Try readng what I wrote. > No revenue product then, I assume. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Jan Panteltje on 30 Sep 2009 17:42 On a sunny day (Wed, 30 Sep 2009 14:29:06 -0700) it happened John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote in <2ni7c5p9qbc73lgra1tcchc8132sui3t5d(a)4ax.com>: Yeah, I suppose so. Spread-spectrum will have to do. It has its own >complications. If I triangle-modulate all the switcher frequencies, I >don't want the triangle to appear on the power rails either. That >could easily happen. Spice? Breadboard? Take a chance? Go linear with >big heat sinks? Big is a relative thing, with your metal housing maybe not even needed. Linear will be quieter. You do not care about wasting Watts, as you previous project proved.
From: Jan Panteltje on 30 Sep 2009 17:44 On a sunny day (Wed, 30 Sep 2009 14:41:34 -0700) it happened Joerg <invalid(a)invalid.invalid> wrote in <7ii1kiF31qi8nU6(a)mid.individual.net>: >Jan Panteltje wrote: >> On a sunny day (Wed, 30 Sep 2009 14:31:10 -0700) it happened Joerg >> <invalid(a)invalid.invalid> wrote in <7ii112F31qi8nU3(a)mid.individual.net>: >> >>> Jan Panteltje wrote: >>>> On a sunny day (Wed, 30 Sep 2009 13:01:31 -0700) it happened Joerg >>>> <invalid(a)invalid.invalid> wrote in <7ihrovF320ev9U2(a)mid.individual.net>: >>>> >>>>>> All depends, 10mV is fine with me:-) >>>>>> >>>>>> You really got to come up with some numbers, else it all makes no sense, >>>>>> >>>>> Ok, this is the number I typically need: Not being able to show the >>>>> ripple on a scope when set to 2mV/div. Good enough? >>>>> >>>>> Seriously, 10mV piping out would be disastrous when doing things like >>>>> ultrasound experiments. >>>> LOL I have done quite interesting ultrasound Doppler experimensts. >>>> If your circuit is so bad that it cannot tolerate 10 mV ripple on the supply line, >>>> then I suggest you change to gardening. >>>> >>> So, then, how many beamformers, audio Dopplers and color flow modules >>> have you brought from blank sheet to market? Experiments, revenue >>> product, two different things. >> >> Try readng what I wrote. >> > >No revenue product then, I assume. You are weaseling away from the subject of 10 mV ripple on supply lines.
From: Nico Coesel on 30 Sep 2009 18:18 John Larkin <jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: >Last time a car went dead in the garage, my wife's Fit, I hacked up a >charger from an old DSL wall-wart and a sabre saw as a series current >limiter. The garage geometry makes it essentially impossible for us to >push a car uphill to the street to jump it. Now The Brat left her Echo >in the garege for a month or so and it went dead, too. So I figure >it's time to buy a real charger. Went to Kragen Auto Parts and bought >two (one for here, one for Truckee) chargers. They are all "smart >chargers", namely switchers with electronics, these days. > >So I went to work and nabbed a cute little Lascar bench power supply. >It current limits at 1.2 amps, so I just cranked it up. The battery >went instantly to 16.5 volts, then settled down to 12 or so in a few >minutes, and is creeping back up. Last time I told you to get an HP 6002A and a series diode! -- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... "If it doesn't fit, use a bigger hammer!" --------------------------------------------------------------
From: Joerg on 30 Sep 2009 18:40
Jan Panteltje wrote: > On a sunny day (Wed, 30 Sep 2009 14:41:34 -0700) it happened Joerg > <invalid(a)invalid.invalid> wrote in <7ii1kiF31qi8nU6(a)mid.individual.net>: > >> Jan Panteltje wrote: >>> On a sunny day (Wed, 30 Sep 2009 14:31:10 -0700) it happened Joerg >>> <invalid(a)invalid.invalid> wrote in <7ii112F31qi8nU3(a)mid.individual.net>: >>> >>>> Jan Panteltje wrote: >>>>> On a sunny day (Wed, 30 Sep 2009 13:01:31 -0700) it happened Joerg >>>>> <invalid(a)invalid.invalid> wrote in <7ihrovF320ev9U2(a)mid.individual.net>: >>>>> >>>>>>> All depends, 10mV is fine with me:-) >>>>>>> >>>>>>> You really got to come up with some numbers, else it all makes no sense, >>>>>>> >>>>>> Ok, this is the number I typically need: Not being able to show the >>>>>> ripple on a scope when set to 2mV/div. Good enough? >>>>>> >>>>>> Seriously, 10mV piping out would be disastrous when doing things like >>>>>> ultrasound experiments. >>>>> LOL I have done quite interesting ultrasound Doppler experimensts. >>>>> If your circuit is so bad that it cannot tolerate 10 mV ripple on the supply line, >>>>> then I suggest you change to gardening. >>>>> >>>> So, then, how many beamformers, audio Dopplers and color flow modules >>>> have you brought from blank sheet to market? Experiments, revenue >>>> product, two different things. >>> Try readng what I wrote. >>> >> No revenue product then, I assume. > > You are weaseling away from the subject of 10 mV ripple on supply lines. No. I said 10mV ripple on supply lines do matter in ultrasound, it's way too much when you must listen to the wee rumbles in the aortoa of an incredibly obese person. I've got well over 20 years in that business. Anyhow, if I bought a lab bench the supply that had 10mV ripple on the output it would go back same day. This is not to diss you PIC solution, that can very well have its place and certainly for experiments with digital stuff. Just not with what I usually do. FYI, one of my recent switchers (30W) has 600uV of ripple under full load. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |