Hello, friends.
Came to my hands JBL Crown A6000GTI with the burned control part. 79l15a and 7915 burned and a high voltage went and took everything in its 15v line. I'm replaced all LM319, IR4427, UC3825, logic chips HC74A(changed to 74HC74), AC04(changed to 74AC04), as well as HIP4081A which tells the power supply. But the power supply still does not start. I have generation at the output of the UC3825 = 450Hz, this line goes to 5,6 pin on the HIP4081 chip, on the 2,7,15,16 pin I have a voltage of 14.9v. 4 PIN is GND. 3rd pin DIS I have a generation of 900 + Hz. if I'm not mistaken, this is a logical level, it is responsible for the open / close outputs oF the chip. but I have nothing on the output of the IC. there is a suspicion that it is educated or burned out from static voltage. Has anyone encountered such an amplifier? can you give recommendations?
On the 3rd pin on the IC HIP4081A
On the output of the UC3825 14,11 pin I have sinus = 450Hz
On the IR4427 on the 2nd and 4 pin i have sinus =125kHz
2ic 4427 al linputs are connected in parallel but outputs gone to 2 transformators
Came to my hands JBL Crown A6000GTI with the burned control part. 79l15a and 7915 burned and a high voltage went and took everything in its 15v line. I'm replaced all LM319, IR4427, UC3825, logic chips HC74A(changed to 74HC74), AC04(changed to 74AC04), as well as HIP4081A which tells the power supply. But the power supply still does not start. I have generation at the output of the UC3825 = 450Hz, this line goes to 5,6 pin on the HIP4081 chip, on the 2,7,15,16 pin I have a voltage of 14.9v. 4 PIN is GND. 3rd pin DIS I have a generation of 900 + Hz. if I'm not mistaken, this is a logical level, it is responsible for the open / close outputs oF the chip. but I have nothing on the output of the IC. there is a suspicion that it is educated or burned out from static voltage. Has anyone encountered such an amplifier? can you give recommendations?
On the 3rd pin on the IC HIP4081A
On the output of the UC3825 14,11 pin I have sinus = 450Hz
On the IR4427 on the 2nd and 4 pin i have sinus =125kHz
2ic 4427 al linputs are connected in parallel but outputs gone to 2 transformators
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Hello Perry. Thanks you. I created theme from telephone and corrected it with PC
place of HIP4081 and UC3825
Transformator has iron ring. And on the dcdc pmw making on the UC3825 friend.
conventional power supplies operate on a ferrite ring and have an operating frequency of 20-35 kHz. The JBL power supply unit has an iron ring and operates at an operating frequency of 450Hz.
According to the datasheet DIS(able) pin 3 is internally pulled high, so you would need to lift the pin and ground it in order to tell if it's being shut down by an external source.
According to the service manual when you apply the remote the 24v supply starts, then the main supply. Do you have +/-24v on the main board? Note: with the audio board disconnected you shouldn't run it for very long, there are 2 capacitors (C53 and C54) which will experience an overvoltage condition when running the supply apart from the audio board. This is only on the -24v side of the low voltage power supply, to avoid any problems I replaced those parts with ones rated for 63v.