Arduino metal detector?

[Prospekteur]

Nice project! I have a few Arduino nano here too. Eventually a nice winterproject;-) Good work!

[bernte_one]

i think you do good work with this fast optocoupler und the mosfet driver ic

[FoxyLab]

...

New version of MOSFET driver:

It combines speed and performance at lower supply voltage.

[FoxyLab]

What results, depth, dicrimination, etc - do you have for this MD so far ?

depth -
discrimination - not
results - see above in this thread
see details here (in russian) - http://acdc.foxylab.com/node/47

[jlsilicon]

What results, depth, dicrimination, etc - do you have for this MD so far ?

[FoxyLab]

My NANO arrived today, cannot believe how small it is.

Little pigeons can carry great messages

[FoxyLab]

Nice project Foxy. I have used the HCPL-3120 before to drive mosfets and they work great. But they have one draw back. There is an under voltage lockout feature which if the battery voltage falls below 11 volts it turns off. There are different versions, some cut off at 10v some at 11v. See data sheet for "UVLO". So use 12 - 14v for your power supply as Foxy did.

Important note. Thanks!
I assembled the stand to test them:

I will check and let you know the results.
P.S. I plan to top-middle of July to prepare a public version foxyPIv2 software.

[6666]

My NANO arrived today, cannot believe how small it is.

[Altra]

Nice project Foxy. I have used the HCPL-3120 before to drive mosfets and they work great. But they have one draw back. There is an under voltage lockout feature which if the battery voltage falls below 11 volts it turns off. There are different versions, some cut off at 10v some at 11v. See data sheet for "UVLO". So use 12 - 14v for your power supply as Foxy did.

[ivconic]

Thanks!
I bought a HCPL chips from this seller on eBay: http://www.ebay.ca/itm/5-PCS-HCPL-31...-/261366995287
Driver v1 - simple circuit, but slow off the MOSFET -> low voltage peak in coil -> low sensitivity (excuse me for my bad english )
Driver v2 - complex circuit, faster off the MOSFET (description of similar circuit in russian http://radiohlam.ru/raznoe/driver_polevikov.htm). I met the description of a similar scheme in the French engineer, but lost the link.
Driver v3 - a simpler scheme than the Driver v2, but sensitivity similar to Driver v2.

Nothing wrong with your English!
Thanks for explanation!

[FoxyLab]

Very well done!
Lot of useful observations on original page.

Thanks!
I bought a HCPL chips from this seller on eBay: http://www.ebay.ca/itm/5-PCS-HCPL-31...-/261366995287
Driver v1 - simple circuit, but slow off the MOSFET -> low voltage peak in coil -> low sensitivity (excuse me for my bad english )
Driver v2 - complex circuit, faster off the MOSFET (description of similar circuit in russian http://radiohlam.ru/raznoe/driver_polevikov.htm). I met the description of a similar scheme in the French engineer, but lost the link.
Driver v3 - a simpler scheme than the Driver v2, but sensitivity similar to Driver v2.

[ivconic]

Very well done!
Lot of useful observations on original page.
Can you explain here all the advantages/disadvantages between the 3 versions of the mosfet driver?
HCPL-3120 is maybe hard to obtain; so i would rather chose version 1 or version 2.
Version 2 looks more interesting.

[6666]

Thanks for update.

[FoxyLab]

My current circuit for foxyPIv2 Arduino-based MD:
(description (in russian) - http://acdc.foxylab.com/node/47 )

[FoxyLab]

400V peak, look good
whats is the longest pulse you can produce without heating the coil driver too much?

I experimented with pulse durations up to 750 usec.
P.S. I got a chip HCPL-3120. My current MOSFET driver circuit: