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Old 21st December 2011, 06:13 PM   #1
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Default HAL SYMFET

Hi RSK,

Here it is. Let members comment for a while then you can build.

kind regards,

Harrison.
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Old 22nd December 2011, 03:07 PM   #2
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Originally Posted by OnAudio View Post

Here it is.
The statement in the schematic that reads "Replace R37 and R38 with a 2k precision trimmer" should read "Replace R37 and R38 with a 1k precision trimmer".
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Old 22nd December 2011, 04:50 PM   #3
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a few more graphs inorder
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Old 22nd December 2011, 09:08 PM   #4
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Quote:
Originally Posted by OnAudio View Post
a few more graphs inorder
Strange way to do square wave test, only positive swing???
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Old 23rd December 2011, 01:57 AM   #5
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Strange way to do square wave test, only positive swing???
Hi Dadod,

Not so strange

kind regards,

Harrison.
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Old 23rd December 2011, 01:59 AM   #6
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Default gate protection diodes

I wonder how much heat the gate protection diodes on these output devices can take ?
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Old 23rd December 2011, 04:08 AM   #7
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Quote:
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Strange way to do square wave test, only positive swing???
Is it not? I mentioned it in his previous design.
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Old 23rd December 2011, 04:19 AM   #8
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Quote:
Originally Posted by OnAudio View Post
I wonder how much heat the gate protection diodes on these output devices can take ?
Why? the device is rated at 150 degrees centigrade, it would be silly if they rated the diodes at any less.
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Old 23rd December 2011, 04:27 AM   #9
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Why use a Vbe multiplier with Lateral Mosfets, that whole arrangement including precision pots can be replaced by a single resistor.

What are the purpose of D9 & D10, the double diode Vdrop will remain the same regardless of the additional noise introduced by the zener.
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Old 23rd December 2011, 06:35 AM   #10
dadod is online now dadod  Croatia
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Originally Posted by OnAudio View Post
Hi Dadod,

Not so strange

kind regards,

Harrison.
OK show us +- swing, or you don't know how to do that?
Use of the bias spreader with laterals is recommended because when trimer loses conntact there is no danger of possible distraction of laterals. Trimer should be connected between base and emitter and bias transistor should not be thermaly bonded with laterals.
dado
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