Good day folks,
I have two different amplifiers with different output FETS and drivers but similar symptoms.
Both amplifiers, no shorts found , both were repaired. when powered up they both go into protect, when checked the HS outputs are shorted G-S, all other outputs test fine. After the rails are discharged, the HS output test open. i've replaced the drivers in both to no avail.
Anyone came across a similar problem?
I have two different amplifiers with different output FETS and drivers but similar symptoms.
- Firstly i have a Soundigital 8k, older silver unit, uses IR2010 gate drivers and IRFGP4072 outputs, came in with burnt power supply.
- Secondly a Soudigital 3k, silver unit, uses IRS20957S and A2 outputs. came in with burnt output filter caps.
Both amplifiers, no shorts found , both were repaired. when powered up they both go into protect, when checked the HS outputs are shorted G-S, all other outputs test fine. After the rails are discharged, the HS output test open. i've replaced the drivers in both to no avail.
Anyone came across a similar problem?
When you read a short g-s, do you also have rail voltage measured directly across the speaker terminals?
Let the bootstap caps to discharge or do it yourself via a 1K resistors. IR drivers mantain the pulldown transistors on when going shutdown to protect output MOS.
Post # 2: no I don't measure rail voltage across the spk terminals, I do have rail voltage (130vdc) at the rectifier)
Post #3: I discharged both bootstrap caps on each driver, the short is still present.
I'm referencing the SD 3K for the remainder of this thread. ( IRS20957S and A2 outputs).
Post #3: I discharged both bootstrap caps on each driver, the short is still present.
I'm referencing the SD 3K for the remainder of this thread. ( IRS20957S and A2 outputs).