So nobody can answer what I have asked? Very simple question: what is resistance between pin 4 (-Vcc), pin 7 (GND) on genuine LM3886?
in resistance mode, with an Agilent 1241B, it measures >4 Mohms, with both polarities.
In 'diode' mode, with (+) Lead on Pin 4 (-Vee) and (-) Lead on pin 7, (GND) -- it shows conductance, with drop 0,65V - one diode drop, (forward junction)
When reversed, with (-) Lead on Pin 4 (-Vee) and (+) Lead on pin 7, (GND) -- it shows 'Open'
reassuming: normal use is that Pin4 is negative supply and GND pin is more positive.
When the GND pin goes more negative than -Vee, than somewhere a diode opens.
So, it could be that your multimeter perceives this forward junction as a low impedance short..
Ciao, George
And his chips visually look like the family of chips with TF package from an italian small webshop in my photos - and those work perfectly in my amps..
but yes, his chips look different than the actual genuine Mouser, RS origin chips in my stack
but yes, his chips look different than the actual genuine Mouser, RS origin chips in my stack
Heh, yes, You are right...
butt... 😜
here it is an older batch.. again faithfully well working..
But most probably it still looks a bit suspicious, Krume's chip
butt... 😜
here it is an older batch.. again faithfully well working..
But most probably it still looks a bit suspicious, Krume's chip
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Many Thanks George! Bad news are good news - definitely fakes, in resistance mode both polarities 2,0 Ohm (short is 0,2 ohm), in diode mode 0,1V in both polarities.
