Searching \ for '[EE]: Widlar Optimisation.. with a voltage booster' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/power.htm?key=voltage
Search entire site for: 'Widlar Optimisation.. with a voltage booster'.

Exact match. Not showing close matches.
PICList Thread
'[EE]: Widlar Optimisation.. with a voltage booster'
2005\08\05@152647 by Philip Pemberton

face picon face

OK, this EPROM refused to program or erase, so I decided to test out my
micro-inverter on it. Basically, the uI is a small box built out of bits of
a Kodak MAX disposable camera flash. It charges a 120uF capacitor up to 200V
and dumps it into the output. The effect on semiconductors is quite
spectacular, and usually involves exploding bond wires and flying silicon.

Basically, this is my variant on the age-old theme of smashing failed ICs to
bits with a very large hammer.

Photos:
 In the middle of the Big Zap:
   <http://www.philpem.me.uk/bigbang/epromboom.jpg>    [  21 Kbytes ]
 The micro-inverter (close-up)
   <http://www.philpem.me.uk/bigbang/inverter.jpg>     [ 367 Kbytes ]
 The EPROM (after blasting)
   <http://www.philpem.me.uk/bigbang/blastedeprom.jpg> [ 815 Kbytes ]

If anyone wants any more info on the "experiment" let me know. I've got CAD
files for the inverter PCB (single-sided 0.8mm, based on the "Rev C" Kodak
flash with an NPN strobe transistor) if anyone wants to build one.

Later.
--
Phil.                              | Acorn RiscPC600 SA220 64MB+6GB 100baseT
spam_OUTphilpemTakeThisOuTspamphilpem.me.uk              | Athlon64 3200+ A8VDeluxe R2 512MB+100GB
http://www.philpem.me.uk/          | Sony MZ-N710 NetMD Minidisc
... A bird in the hand is safer than one overhead.

2005\08\05@160218 by Harold Hallikainen

face picon face
Wow! A solid state flash bulb!

HH


{Quote hidden}

--
FCC Rules Updated Daily at http://www.hallikainen.com

2005\08\05@202831 by Hector Martin

flavicon
face
Mmmm... High voltage destruction! My favorite!

I've got a 400V cap lying around. Might give it a shot *grin*


Philip Pemberton wrote:
{Quote hidden}

--
Hector Martin (.....hectorKILLspamspam@spam@marcansoft.com)
Public Key: http://www.marcansoft.com/hector.asc

2005\08\05@202941 by Hector Martin

flavicon
face
BTW, why use an inverter at all? Just wire it up to the mains plug
with a fuse and diode and a current-limit resistor. I've seen someone
try that, and it works fine for charging.


--
Hector Martin (hectorspamKILLspammarcansoft.com)
Public Key: http://www.marcansoft.com/hector.asc

2005\08\06@035529 by Philip Pemberton

face picon face
In message <.....42F40475.3010202KILLspamspam.....marcansoft.com>
         Hector Martin <EraseMEhectorspam_OUTspamTakeThisOuTmarcansoft.com> wrote:

> BTW, why use an inverter at all? Just wire it up to the mains plug
> with a fuse and diode and a current-limit resistor. I've seen someone
> try that, and it works fine for charging.

Well, there's the fact that the 240V UK mains can pump out a serious amount
of current - well into the dozens of amps range. The inverter pumps out a few
mA and is a hell of a lot safer as a result...

Of course, adding the capacitor negates that argument to some degree...

Later.
--
Phil.                              | Acorn RiscPC600 SA220 64MB+6GB 100baseT
philpemspamspam_OUTphilpem.me.uk              | Athlon64 3200+ A8VDeluxe R2 512MB+100GB
http://www.philpem.me.uk/          | Sony MZ-N710 NetMD Minidisc
... I'm not nearly as think as you confused I am.

2005\08\06@184039 by Juan Cubillo

flavicon
face
> > If anyone wants any more info on the "experiment" let me know.

Could you please send me the files for the "experiment"
Thnkz


2005\08\08@045638 by Alan B. Pearce

face picon face
>Mmmm... High voltage destruction! My favorite!
>
>I've got a 400V cap lying around. Might give it a shot *grin*

Next you lot will be putting such discharges through 3" transistor speaker
voice coils. I believe if done with the correct polarity the missile effect
is amusing.

2005\08\08@050056 by Alan B. Pearce

face picon face
>> BTW, why use an inverter at all? Just wire it up to the mains
>> plug with a fuse and diode and a current-limit resistor. I've
>> seen someone try that, and it works fine for charging.
>
>Well, there's the fact that the 240V UK mains can pump out a
>serious amount of current - well into the dozens of amps range.
>The inverter pumps out a few mA and is a hell of a lot safer as a result...

A lot of people seem to forget that the mains supply is probably about as
close as you will ever see, to a perfect voltage source - at least as far as
the socket in your house is concerned.

2005\08\08@063222 by Russell McMahon

face
flavicon
face
> A lot of people seem to forget that the mains supply is probably
> about as
> close as you will ever see, to a perfect voltage source - at least
> as far as
> the socket in your house is concerned.

It's also an excellent approximation to a perfect current source for
loads below about 0.1 ohm - but not for long :-).



           RM

2005\08\08@063731 by Howard Winter

face
flavicon
picon face
Alan,

On Mon, 8 Aug 2005 10:00:52 +0100, Alan B. Pearce wrote:

> >Well, there's the fact that the 240V UK mains can pump out a
> >serious amount of current - well into the dozens of amps range.
> >The inverter pumps out a few mA and is a hell of a lot safer as a result...
>
> A lot of people seem to forget that the mains supply is probably about as
> close as you will ever see, to a perfect voltage source - at least as far as
> the socket in your house is concerned.

As long as you kept to the wiring regulations when you did your DIY rewire!  :-)  

In the US, where they have less voltage to start with, the wiring seems more prone to lights dimming when you
turn on something hefty.  At my girlfriend's house in New York, I measured a 7 Volt drop at the dining-room
sockets when the microwave is running in the kitchen - this is 7V out of 110V, of course, so quite noticeable.  
And this is a sustained drop, not just a momentary dip, it carries on until the microwave turns off.  Whether
this is due to the old (aluminium) wiring or something else, I don't know.

Cheers,


Howard Winter
St.Albans, England


2005\08\08@065446 by Howard Winter

face
flavicon
picon face
Russell,

On Mon, 08 Aug 2005 22:32:12 +1200, Russell McMahon wrote:

> > A lot of people seem to forget that the mains supply is probably
> > about as
> > close as you will ever see, to a perfect voltage source - at least
> > as far as
> > the socket in your house is concerned.
>
> It's also an excellent approximation to a perfect current source for
> loads below about 0.1 ohm - but not for long :-).

Actually it's pretty good up to about an ohm round these parts! :-)

It amuses me that the breaking capacity of a 6A Miniature Circuit Breaker (MCB), used for lighting circuits
here, is 6kA (yes, six thousand amps).  I can't help thinking that the cables it's feeding, usually 1.5mm^2,
would be vapour long before the MCB had a chance to trip at that sort of current!

Cheers,


Howard Winter
St.Albans, England


2005\08\08@071251 by Jinx

face picon face
> At my girlfriend's house in New York, I measured a 7 Volt
> drop at the dining-room sockets when the microwave is
> running in the kitchen

Sigh, you're just a plain ole-fashioned romantic aren't you
Howard ? A box of chocs, some roses and a Fluke. Do
you offer this "service" in restaurants too ;-)

A friend of mine is having a battle with one of the Auckland
electricity suppliers. His lights (and those in other suburbs he
tells me) flicker. The first time I was at his place I thought
there was a moth fluttering around the bulb, it's that noticeable.
Apparently there's a major consumer causing voltage dips in
vast swathes of housing

2005\08\08@101743 by Mike Hord

picon face
> In the US, where they have less voltage to start with, the wiring seems
>more prone to lights dimming when you
> turn on something hefty.  

Ayup.  My office (for various reasons) also happens to be the "break room"
(which is to say, the coffee pot, microwave, and full-size refrigerator are in
here, and it's the only room where food or drink is officially allowed), and
when the compressor in fridge kicks on, I tend to lose RPMs on the drill,
temp on the soldering iron or heat gun, and a little light.

I'm lobbying for a different office.

Mike H.

2005\08\09@082104 by Howard Winter

face
flavicon
picon face
Mike,

On Mon, 8 Aug 2005 09:17:43 -0500, Mike Hord wrote:

> > In the US, where they have less voltage to start with, the wiring seems
> >more prone to lights dimming when you
> > turn on something hefty.  
>
> Ayup.  My office (for various reasons) also happens to be the "break room"
> (which is to say, the coffee pot, microwave, and full-size refrigerator are in
> here, and it's the only room where food or drink is officially allowed), and
> when the compressor in fridge kicks on, I tend to lose RPMs on the drill,
> temp on the soldering iron or heat gun, and a little light.

LOL!  What is the allowable voltage drop there?  (Installations here are allowed 3% I believe - just under 7V
at 230V).

> I'm lobbying for a different office.

Couldn't you just lobby for a seperate power feed?

Cheers,




Howard Winter
St.Albans, England


2005\08\09@084341 by Michael Rigby-Jones

picon face


{Quote hidden}

Sounds like you have a good case if you are drilling and soldering in a food preparation area!

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.
=======================================================================

2005\08\09@092633 by Mike Hord

picon face
> > > In the US, where they have less voltage to start with, the wiring seems
> > >more prone to lights dimming when you
> > > turn on something hefty.
> >
> > Ayup.  My office (for various reasons) also happens to be the "break room"
> > (which is to say, the coffee pot, microwave, and full-size refrigerator are in
> > here, and it's the only room where food or drink is officially allowed), and
> > when the compressor in fridge kicks on, I tend to lose RPMs on the drill,
> > temp on the soldering iron or heat gun, and a little light.
>
> LOL!  What is the allowable voltage drop there?  (Installations here
> are allowed 3% I believe - just under 7V at 230V).

Others would know this better than I; I'd be fairly certain I'm exceeding it
here.  Especially if someone is running the coffee maker and microwave,
too!

> > I'm lobbying for a different office.
>
> Couldn't you just lobby for a seperate power feed?

I could, but the alternate office is more likely in the near future.  It'd
give me much needed stretching room, too; my 4 meters of bench
space is quite inadequate.

Mike H.

2005\08\09@092955 by Mike Hord

picon face
> >I'm lobbying for a different office.
> >
> >Mike H.
>
> Sounds like you have a good case if you are drilling and
> soldering in a food preparation area!

Other side of the room. ;-)

Actually, though, you are right.  For example, when I etch
PCBs, which sink do I have to use?

These are concerns I have, but basically, there's nothing I
can do about them.  I just have to clean up after myself,
very well, and not do this stuff when people are making
food near at hand.  Other less-than-foodsafe things go on
at that sink, too, since this room is used by many others
for many things other than eating.

Mike H.

2005\08\09@095450 by Alan B. Pearce

face picon face
>Other less-than-foodsafe things go on at that sink,
>too, since this room is used by many others for
>many things other than eating.

I take it you don't have lunch in the office then ;)

2005\08\09@095915 by Dave Lag

picon face
IIRC- NEC/CEC tables show max length of runs for a 5% drop, would assume
that the maximum voltage drop recommended.
D

Mike Hord wrote:

>>LOL!  What is the allowable voltage drop there?  (Installations here
>>are allowed 3% I believe - just under 7V at 230V).

> Others would know this better than I; I'd be fairly certain I'm exceeding it
> here.  Especially if someone is running the coffee maker and microwave,
> too!
>
> Mike H.


More... (looser matching)
- Last day of these posts
- In 2005 , 2006 only
- Today
- New search...