MMATS D2000.2

[S Merlington]

Well that would explain the power supply issue

 

[S Merlington]

I put a Mic4424 in the socket and the power light lights up now but the amp draws excessive current and fets heat up within 2 secs

The outputs are out of the amp right now also the hip 4080 is out

Any ideas?

 

[Perry Babin]

Post a photo of the board.

 

[S Merlington]

I gotta run and get a new camera cord later so i can post a pic..

Heres what i have on the Sg3525 now do theese voltages apper corret or is there an issue


Pin 1:2.13
Pin 2:5.14
Pin 3:0.00
Pin 4:1.08
Pin 5:1.80
Pin 6:3.80
Pin 7:1.82
Pin 8:0.47
Pin 9:6.00
Pin 10:0.00
Pin 11:0.00
Pin 12:0.00
Pin 13:13.13
Pin 14:0.00
Pin 15:0.00
Pin 16:5.14

Heres what i get on the MIC4424

Pin 1:0.00
Pin 2:0.00
Pin 3:0.00
Pin 4:0.00
Pin 5:0.00
Pin 6:0.00
Pin 7:13.12
Pin 8:0.00

Im not sure if its the right driver ic or not..

Heres what i get

Pin 11 of the Sg3525 would connect to PIn 4 of the driver IC
Pin 14 would connect to PIN 2


Pin 3 of the Driver IC would be connected to ground
Pin 8 of the Driver IC would connect to the Gate Leg of the Power supply fets
Pin 3 of the Driver IC would connect to the source leg of the power supply fets

The drain Leg of the Fet would connect to the emitter of an 2N4403

Does this make sense and does it apper that thats the correct driver IC and do the voltages apper to be right or is there something wrong ?

 

[Perry Babin]

I wouldn't expect the FETs to be heating up. There is no drive voltage.

 

[S Merlington]

The fets dont heat up at all now amp doesnt power up

 

[Perry Babin]

I think that there is at least one mistake with the voltages on the 3525. Recheck them. Pin 15 would have to be at at least 8v to have 5v on pin 16.

 

[S Merlington]

SG3525

Pin 1:0.00
Pin 2:5.14
Pin 3:0.00
Pin 4:1.08
Pin 5:1.79
Pin 6:3.79
Pin 7:1.71
Pin 8:0.48
Pin 9:6.00
Pin 10:0.00
Pin 11:0.00
Pin 12:0.00
Pin 13:13.13
Pin 14:0.00
Pin 15:13.13
Pin 16:5.14

 

[Perry Babin]

Pin 8 isn't high enough. It should be near 5v. This is the soft-start terminal. An internal constant-current source charges an external capacitor. The most likely problems are a leaky cap, a defective CCS inside the IC or possibly an external component holding it down.

Pin 4 also is a bit higher than normal but that may be because the output is shut down.