I don't know for certain. They look like the MIC4420 type drivers. Previous post:
Digital Designs Z2b driver
Digital Designs Z2b driver
upon reading the Digital Designs post and reading the data sheet i'm not sure about which ones they used. either non-inverting or inverting drivers. and if both are used which position they are used in. Or if they only use one of the two and just use double up for each set of outputs.
MIC4420zt non-inverting
MIC4429zt inverting
MIC4420zt non-inverting
MIC4429zt inverting
yes the ground legs do attach to the source leg of the fet they are driving.
The output leg connects the set of fets through a resistor and diode that are parallel with each other. i have uploaded a pic to show what i am describing.
Even with all fets removed on this side I was showing a short between the gate and the positive rail. i removed one leg of all the gate resistors and still had the short while measuring the other leg and the rail. Ended up being D54a shorted.
The output leg connects the set of fets through a resistor and diode that are parallel with each other. i have uploaded a pic to show what i am describing.
Even with all fets removed on this side I was showing a short between the gate and the positive rail. i removed one leg of all the gate resistors and still had the short while measuring the other leg and the rail. Ended up being D54a shorted.
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I would think that both are non-inverting.
To check (both) remove them from the board.
Connect the Vs input to 12v (via a 1 ohm 1/4w resistor to protect the IC).
Connect the ground to the 12v PS ground.
Connect the input to a 10k resistor (not critical).
When you touch the 10k resistor to the Vs input (12v) of the IC, the output pin should follow (go to 12v).
To check (both) remove them from the board.
Connect the Vs input to 12v (via a 1 ohm 1/4w resistor to protect the IC).
Connect the ground to the 12v PS ground.
Connect the input to a 10k resistor (not critical).
When you touch the 10k resistor to the Vs input (12v) of the IC, the output pin should follow (go to 12v).
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One without a doubt was bad. It showed to be shorted on all legs. The other passed the procedure that you gave Perry. I would still feel better replacing both as the other may be weakened. I forgot to mark the audio driver cards as to which side each came out of. So i will use the empty side where i have removed all the fets to see if i have good drive signal from each. Elderly moment.
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