Cute new part: LMG5126

TI is doing some cool GaN stuff lately. We were considering using their LMG2100R044, which is a 100v 35a half-bridge, but it was overkill for our little project. Still, it's impressive.

I have a summer intern, a really smart kid, and one of his projects is to make a high voltage pulse generator using power GaN fets. There are some 700v parts around now.

What will you do about the transformer?

The local Coilcraft guy is coming over this morning. He could buy us lunch.

Their planar transformers could be made into some screaming fast parts.

Nice day for it, according to Accuweather.(*)

For 0.01% of their customers. ;)

What I want it for is all unipolar, so just the fast regulator plus a linear stage is the ticket.

I might use something like a 48V POE supply and buck down to do the same thing.

Cheers

Phil Hobbs

(*) As an aside, is Accuweather as uniformly pessimistic where you are? In NY it's always predicting clouds and rain, which frequently don't show up, and when the do, usually aren't nearly so dreary as they claim.

We're hoping it might get up to 60F today.

Sunday was Gay Freezing Day here. Sequins turn out to be not very good thermal insulation.

Megahertz GaN power is a big deal lately. They need small, low loss, well shielded transformers.

We're using the Silvertel PoE pickoff brick. I could share schematics.

We're in the Alamany Gap microclimate. It's a cold fog channel between the ocean and the bay.

Yes, same in Boston (and likely everywhere), because people complain more about having their picnic rained out than if the warning was wrong.

My favorite is Clime NOAA, which works worldwide. You do pay about $40 per year, so Clime can purchase the realtime radar and satellite data feeds.

With Clime, you decide the optimism/pessimism balance.

.

Joe

It doesn't rain here between March and November.

We rarely get thunderstorms or see lightning, less than once a year. We get more earthquakes than thunderstorms. Pity, I used to enjoy thunderstorms.

It doesn't stop raining here between November and March. (...except when it snows.)

I had a motorcycle in New Orleans. It would reliably rain hard between about 1 and 3 PM most every day, but I could bike to/from work.

If I got caught once in a while, it was nice warm rain.

In Truckee, up in the mountains, it can snow any day of the year. I skiied Sugar Bowl once on the 4th of July.

Probably with nickel-zinc ferrite cores. Manganese-zinc is a bit too conductive for megahertz switching frequencies.

That used to be the case - more or less - but not now in most of the south and east of England. We have near drought conditions here in south Hampshire; the total rainfall for the first 6 months of this year is just under 300mm:

Jan 128.7 Feb 72.4 Mar 8.9 Apr 32.3 May 14.4 Jun 43.0

If you omit January, we've had seven inches of rain in five months, and we're not so badly off as some of those in East Anglia.

English Winter 'rain' is rarely pleasant. We tend to have long spells of cold drizzle that chills to the bone and eventually penetrates to the insides of houses, making them clammy and damp if they aren't heated well (which is very expensive). Nothing ever gets properly dry for weeks or even months on end.

Dry snow is a rarity as the temperatures usually hover just above and just below freezing, so the snow is wet and slushy. Warm rain sometimes occurs - but only in Summer.

That explains why the English colonized India and Africa and the Carribean. They were cold.

It must have been dreadful before waterproof synthetics and stuff like Thinsulate were invented. When clothing was so expensive that people were killed for their clothes and here were no electric dryers.

My grammy had a wood stove and hung her wet laundry outside to dry. If it was cold and rainy for a few days, it got moldy stinky and had to be washed again. By hand. Women used to average hours per day on sewing and laundry.

In New Orleans as kids we would put on shorts and tee shirts and go for barefoot walks in the rain. The puddles on the sidewalks would be warm water. It was fun.

It never snows in San Francisco. My neighborhood is almost always cool and often foggy, when a mile away is pleasant and sunny. The gradient in any inland direction from my house can be as much as 2 degF per mile.

The Coilcraft rep bought is sandwiches and we ate outdoors at our "conference room", a random cluster of old chairs and benches near the Arlington Triangle. Our theory is that outdoor meetings have better dynamics than in closed conference rooms. It's the eyeball effect.

They are doing some new low-inductance low-resistance high-frequency inductors moulded from powdered iron instead of epoxy, for GaN type high-current switchers.

Wax-impregnated cotton is fairly waterproof as long as it is re-treated every year. Wool is good for insulation (so is fur, if you are rich), so the traditional combination of cotton underwear for sweat absorbtion, wool for insulation and waxed-cotton outer clothing for weatherproofing worked quite well.

One of my most useful emergency garments is a waterproof overskirt. It can be worn over a skirt or trousers and can be put on by pulling it over your head, so it doesn't drag wet from the ground up over your clothes like overtrousers would. It was made from an offcut of a tent I was making and happens to be waterproof rip-stop nylon, but a lightweight waxed-cotton material would be just as effective. I don't know why more people don't carry them; mine takes up very little space in my bag.