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hawui1
03-Mar-09, 23:06
The new AMP7 appears to need a +5V that can be obtained by feeding 8 to 12V to the on-board regulator (and for this I'm set, I already have a +12V to be used for this purpose), and a 10V-250mA referred to the negative rail of the power supply. Assuming I already have the +/-60 stabilized voltage, is there anybody that could suggest a circuit to obtain this additional 10V referred to -Vss?
more10
03-Mar-09, 23:29
ps2-single does the job.
hawui1
04-Mar-09, 14:12
And how would you connect it to get the VN10?
V-bro
04-Mar-09, 15:25
quote:Originally posted by hawui1

And how would you connect it to get the VN10?


There's an on board connector where PS2 fits in exactly...:) (it's a three hole "header pin style" or "TO-220 style" footprint....)

------X-max. can be several meters on any driver, too bad it can be done only once...------
hawui1
04-Mar-09, 21:53
perfect ! this is very nice news..
So I will have the main rails +60V GND and -60V then I have another +12V referred to the same GND as the main rails and I will use it for the 5V (by connecting +12V and GND) and then there's this connector for the PS2-Single (I just bought) and that's it?

Is there any problem if the +12V I have and I would like to use for 5V is referred to the same GND as the two main rails?
V-bro
04-Mar-09, 22:13
quote:Originally posted by hawui1

perfect ! this is very nice news..
So I will have the main rails +60V GND and -60V then I have another +12V referred to the same GND as the main rails and I will use it for the 5V (by connecting +12V and GND) and then there's this connector for the PS2-Single (I just bought) and that's it?

Is there any problem if the +12V I have and I would like to use for 5V is referred to the same GND as the two main rails?


You've got that all right except the 12V ground. On AMP7 there's a separate input for this 12V which leads into the 5V final regulator circuit. The ground of this input is signal ground (which it should be for the 5V) The signal ground is connected to a star ground under the chip and there's one lead from the star ground connected to power ground through a small inductor.

------X-max. can be several meters on any driver, too bad it can be done only once...------
hawui1
04-Mar-09, 23:02
Ok, so we need a 12V that has a ground that is not common with the GND of the main rails +60V|GND|-60V..It has to be floating.. right? (or the small inductor would be shorted)..
V-bro
05-Mar-09, 08:40
Indeed, but it might work though possibly introducing more noise...

------X-max. can be several meters on any driver, too bad it can be done only once...------
abelma
05-Mar-09, 10:00
I think that the auxiliary +-12Vdc in your SMPS has a isolated ground from the main GND. You could check with your instruments.
hawui1
05-Mar-09, 21:26
Yep Abel, it is insulated (is also clearly specified in the datasheet of the SPS80) just wanted to know if it had to be remain insulated or I had to bind it with the main GND (the former the correct one), so far it appears I'm perfectly set.. the floating 12V will serve the digital 5V while the PS2-Single will produce VN10. Thankyou for the help ;)