And then you have large companies where you write to a provided email link, asking a question where it's obvious that major sales volume could result, get no response, ask at another email address, get no response. Recently happened at ON Semi, a manufacturer whose parts I otherwise really like. Sad. All the while everyone laments about the economy :-(
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
It's a Microchip charge pump regulator. Using two, one to provide
3.3VDC for most of the circuit, and one to boost the LED drive to a constant current of 20mA. Although, I am thinking of lowering that to 12mA to give more life...Charlie
Googling on MC1253 yields nada... You typo'd... it's MCP1253 :-)
Just put an NPN in the ground feed. ...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 |
The only thing bipartisan in this country is hypocrisy
Cowards: No V/I characteristics around zero.
Hides a potential can of worms.
..... the normally-off synchronous rectifier has been a bee in my bonnet for a long time.
RL
m I
he
Joerg, you big spender! Use an n-FET--they're better and cheaper--in the ground lead.
-- Cheers, James Arthur
Yup, that's what I'd do in this case :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Where do you get a discrete NMOSFET that will be thoroughly on at 1.8V VGS?
The Micrel part _may_ work. ...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 |
The only thing bipartisan in this country is hypocrisy
Here's one:
Does n-channel still offer a cost advantage over p-channel for very low voltage devices?
Here's a p-channel device with 113m ohm at 1.2V Vgs.
Apparently a SC-70 can dissipate 19W if you can hold the case to
25°C...
Plenty of others. If it has to be cheap (and somehow it always has to be...), here's an example at around 15 cents, Rdson guaranteed down to 1.5V:
You need to get out into the world of discretes some more :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
[snip]
I don't think so...
It appears that the N-channel part is made on an P-substrate and vice-versa.
[snip]Nice devices! ...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 |
The only thing bipartisan in this country is hypocrisy
Nope! I avoid markets that are priced like popcorn.
Except for my own G-jobs :-) ...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 |
The only thing bipartisan in this country is hypocrisy
Oh, it's not always that way. Roughly half of my designs aren't required to be rock-bottom in BOM cost. Although I can't help it, the calculator in my head is always running. Sometimes clients are surprised when they see the (working) circuit. "You mean, that's it?"
[...]-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
I get that all the time. I really enjoy finding clever solutions to difficult problems. If I ever lose that capability I'll simply self-dispatch :-) ...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 |
The only thing bipartisan in this country is hypocrisy
That's squarely against my religious beliefs. Life doesn't end with Alzheimers and the like. In fact, our new canine addition (former guide dog trainee, hopefully passes therapy dog cert after Easter) will have one such case very soon. And already has served in that area.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Young buck say to old buck: N-channel mostly less bucks for same bang :-)
I don't have much in examples anymore because the notes about p-channel candidates where used to kindle the wood stove. But it happened time and again when I thought about push-pull drivers and two n-channels plus bootstrap was the better deal (financially).
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
1.5V:
I only believe in myself, so I have no such problem :-) ...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 |
The only thing bipartisan in this country is hypocrisy
That was true in the past. Now-a-days I see no rationale for a price difference except for "what the market will bear" :-) ...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 |
The only thing bipartisan in this country is hypocrisy
There really is a penalty. Yeah, initially the difference may seem tiny or zilch but if you want a P-channel with the same performance as the N-channel and not just 70%, very different thing.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
1.5V:
Then you'll have a (huge) problem after you die ;-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
1.5V:
I promise to not be "greasy" :-) ...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 |
The only thing bipartisan in this country is hypocrisy
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.