AC/DC Inductor less desing for 2W at about 10VDC

AC-DC Power Converters
1

I am looking for part recommendation for AC/DC for a 2Watt load.
I need to be able to operate at 120C in a sealed enclosure.
I can use walls of heat sink if they would even help at that temp.
I need to make measurements (frequency and peek) off the input AC as well, so I many need to connect GND to Neutral.
Inductor are an issue as to temp range and shock and vibration I have to deal with.

2

120C is expecting a bit much… How long do you expect the electronics to last?
Also… Which country? Some countries run a MEN’s electrical system, in which case neutral is connected to earth in the switch board, however if there are any RCD’s it will cause a trip.
Note: most AC/DC implementations are only 80% efficient at best so that is heat you can’t afford
Technically you have about a 5C allowance for you electronics which is going to cost, you will be talking military grade and even then few companies will guarantee it will work for long at that temperature.
My first suggestion is to move what ever this is away from the boiler (or whatever is 120C) and start the design again.
If you do connect the PCB GND to neutral, then the unit will no longer be SELV so you need to take appropriate protection (and isolation barrier)

3

This will be used on the output for Air Craft Generator with a Neutral to check its frequency.
The 120C has a test time of 50 hours run time.
The output of the box is a relay which is isolated. No chance of any safety issues.

4

Hi john.zigrang,

Thanks for your question.
We have a few HV Inductor-less Buck Regulators that support your output power.
(I’d recommend selecting a Pout of at least 3-4W to accommodate for your high operating temp.)
Please check the parametric search here: High Voltage Buck Regulators 10W | MPS | Monolithic Power Systems

Also, we don’t usually road test our parts at 120C, so we cannot guarantee the part to function at that temperature. Each datasheet will state a junction temperature (usually ~125C), since we know ambient temp runs higher than junction temp, we can assume the part may not operate at 120C or might go into thermal shutdown mode.

However, the best way to test this is to use the regulator evaluation board and see if the part operates at your desired temperature.

Thanks,
Cindy