rms to dc converter

[ed]

wos occurin?

when I built the first sig gen back in 2013 I used AD536 to convert the raw ac out of the wien bridge to dc so that the atmel could read the voltage. The ad536 was about £11.

move on 9 years.....RS want £72 for the chip if I buy 25 of them...and there is a different package version for £40....

does anybody know of a RMS to DC converter about 20mv to 20v pk-pk that is not silly money?

[Nick]

Well there is the LTC1966, but its only good to 1kHz, and its one of the many parts that you cant buy ATM.

[Nick]

And without knowing what you mean by silly money, there is AD736 that RS seem to have for £20.

[ed]

thanks Nick..I was looking at the 736 yesterday and had pencilled it in as it was the only thing I could find

...but I was just sounding off about the enormous hike on the 536.

there had to be a slim chance there was something cheaper.....

Things here move at glacial speed and I've only just got around to revisiting the unfinished sig gen version 3 for which I had boards made 12 months ago. I've discovered that I completely forgot about the output voltage measurement so I'll have to break into the board to add the output of the 736 to the track for voltage measurement.....

silly money? do you have to ask? cheapskatesRus are now evencheaperskatesRus since my pension collapsed a bit back.

I was watching Steve's thread which got round to boutique caps and was amused to think of the difference between my JB caps in the triangle speakers to the Mundorfs. Mine are £2.10, the Mundorfs would be £21.00. I have to convince myself that I couldn't tell the difference....

[ed]

my apologies for wasting everybodies time.....

I've just found the BOM for signal generator version 3 dated 8.12.21.
It shows AD737..which are currently about £14.....

it would seem that 7 months ago I knew exactly what I was doing...and sometime between then and now I consigned all the info(including the whereabouts of the notes) to the metaphorical bin....

[simon]

Surely one of the best things about getting older is the opportunity to enjoy again something one's forgotten all about

[pre65]

Surely one of the best things about getting older is the opportunity to enjoy again something one's forgotten all about

You might not think it's such a good thing when you get there Simon.

[andrew Ivimey]

Trouble is.... you've forgotten what was you wanted to remember....

[simon]

Already there Phil! No hope for me.

[pre65]

Already there Phil! No hope for me.

[ed]

it gets worse.....

I built a new pc sometime back and omitted to copy the designspark stuff from the old machine.

I loaded the disc from the old machine and checked the designspark stuff and it all started to come back to me...

post #18 in this thread:
https://www.audio-talk.co.uk/phpBB3/vie ... 8&start=22

it seems I didn't send off the gerbers to pcbway, must have been distracted.

I was very nearly ready to redesign the whole thing. Oh waily waily

edit: only difference will be the TL082 will now be a TLE2072

[Paul Barker]

Trouble is.... you've forgotten what was you wanted to remember....

I ordered some chemical off ebay for a purpose, I’ve forgotten. It stands on the shelf waiting for my brain to release the knowledge. 3 months and counting!

[pre65]

Trouble is.... you've forgotten what was you wanted to remember....

I ordered some chemical off ebay for a purpose, I’ve forgotten. It stands on the shelf waiting for my brain to release the knowledge. 3 months and counting!

What chemical was it ?

Perhaps we can help you remember.

[ed]

AAAAaarrrrrggghhhhhh....

more digging and it seems there was a new design for sig gen, dated 1 day later than the one in the sig gen thread...09.12.21

sig gen4.jpg (190.14 KiB) Viewed 2358 times

it would seem that I replaced the JCE03 with TEC 3-2419 dc -dc isolator. I'm not sure why at this stage but I think I'd better go over the pcb design again before sending it off to pcbway.

If you can offer anything to this Nick I'd be grateful as I think it was you that recommended the isolator.....

I will pick this up again in the sig gen thread.

[Nick]

I vaguely remember pointing to an isolated converter, but beyond that I am as in the clouds as you Ed