Autotek MM4000.1

[S Merlington]

The gate resistors for the outputs are 47 ohm and 100k ohm

Does anyone know the wattage of the 47 ohm resistor are they 2 watt ?

 

[timwebb]

1/2 watt i think

 

[Perry Babin]

Measure them and buy the same size.

 

[S Merlington]

I found the KIA7805L to be defective.. T092 package..

I orderd the L7805ACP as replacement ..


Is the pin config the same or do i need to insall it backwards ?

 

[seankane]

You should be able to look up the data sheet for both and confirm the answer to your question.

 

[S Merlington]

Ok replaced the outputs gate resistors and the 5 volt regulator..

What would cause the outputs to blow the faces off them with no driverboards installed??

 

[Perry Babin]

Confirm that you read 2x the gate resistor value between the gate legs of all of the parallel transistors for each group. Place the probe as close to the body of the transistor as possible when measuring the resistance. You'll have to remove the defective output transistors and measure from pad to pad for the defective transistors.

 

[S Merlington]

Yes the value is 2x from pad to pad..

They are 47 ohm resistors if i jump pad to pad i get 92.6 ohms for the paralell outputs

 

[Perry Babin]

The 100k pulldown resistors should prevent the outputs from passing current unless there is a solder bridge that's causing them to be driven 'on'.

Check VERY carefully to confirm that there are no broken connections between pads and traces for the gate and pulldown resistors.