After waiting almost a month for parts I finally have full on switching everywhere it needs to be, all the way to output FETs, everything looks nice and clean, couldn’t be happier. I install Output FETs and amp now cycles in and out of protect.
Original problem was blown Power Supply FETs, taking out the 072 & 2110 on Output Riser card. I replaced all. Amp powers up perfect without Output FETs in, idles @ 1A, but with Output FETs installed it boots as follows:
PSU goes into CC mode while building rail voltage (same wether limited to 3A or 10A) until about -60Volts is built up, then I hear some kind of click near output section, current pull drops to a few mA, rail voltage drops to about -15V, and process restarts, cycling like that.
I haven’t let it cycle more then a few times, not trying to damage anything, I am being way over cautious though because of how long I had to wait on parts. I’m not to familiar with over current circuits, this is the 1st I will be working on actually. I’m assuming that is the problem.
I’ve reflowed the Over current protection rails just in case, don’t know the next step from here, hoping to have some advise on some direction.
Thank you 🖖🏼 Posted a few pics of each of the sections waves just cause. Looks like rail voltage builds up to about -95/-100 volts on this amp I think. My Scope is off by about 5/7.5 in the 50v/100v /div range
Original problem was blown Power Supply FETs, taking out the 072 & 2110 on Output Riser card. I replaced all. Amp powers up perfect without Output FETs in, idles @ 1A, but with Output FETs installed it boots as follows:
PSU goes into CC mode while building rail voltage (same wether limited to 3A or 10A) until about -60Volts is built up, then I hear some kind of click near output section, current pull drops to a few mA, rail voltage drops to about -15V, and process restarts, cycling like that.
I haven’t let it cycle more then a few times, not trying to damage anything, I am being way over cautious though because of how long I had to wait on parts. I’m not to familiar with over current circuits, this is the 1st I will be working on actually. I’m assuming that is the problem.
I’ve reflowed the Over current protection rails just in case, don’t know the next step from here, hoping to have some advise on some direction.
Thank you 🖖🏼 Posted a few pics of each of the sections waves just cause. Looks like rail voltage builds up to about -95/-100 volts on this amp I think. My Scope is off by about 5/7.5 in the 50v/100v /div range
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What are you referring to as:
Over current protection rails
Does the amp power up with the audio driver board out of the circuit?
Over current protection rails
Does the amp power up with the audio driver board out of the circuit?
Pic of OCP rails, R381-R385. Click sound as protect kicks in comes from this area?
I will try removing Output riser card now and note everything.
Before repair I only saw waves on the 393, 072 and 2110 dead in the water in riser card, now I get full on switching everywhere, waves on each In and Out proper for each chip, very clean. I can also record a video if need be. Also of note I think is the way the LEDs cycle, I also have an XTR750.4 that when powered goes straight to Green on only, on this 2500.1 all 3 lit up, then 2, then 1 (Green power on) when I hear click and rail drops protect LED comes on, but goes back off while rail building, clike that. But that may be due to Class A/B full range vs Class D monoblock?
Goodmorning btw Perry 🙂
I will try removing Output riser card now and note everything.
Before repair I only saw waves on the 393, 072 and 2110 dead in the water in riser card, now I get full on switching everywhere, waves on each In and Out proper for each chip, very clean. I can also record a video if need be. Also of note I think is the way the LEDs cycle, I also have an XTR750.4 that when powered goes straight to Green on only, on this 2500.1 all 3 lit up, then 2, then 1 (Green power on) when I hear click and rail drops protect LED comes on, but goes back off while rail building, clike that. But that may be due to Class A/B full range vs Class D monoblock?
Goodmorning btw Perry 🙂
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Without riser card installed rail builds up to about 60Volts, green only led, psu in CC mode but just stops charging at 60Volts but PSU still in constant current mode
Those aren't rails. They are resistors, being used as shunt resistors in this circuit. I've never seen any with bad solder connections.
Which of the heatsink mounted parts get hot when it tries to power up? Leave power connected until one or more of the components starts to get hot.
Which of the heatsink mounted parts get hot when it tries to power up? Leave power connected until one or more of the components starts to get hot.
Ahh ok, ty for clarifying that.
D72, Out rectifier, only one that starts to generate heat. The rest of the FETs stay dead cold.
Can’t wait to finally get a thermal imaging cam, anyone selling one cheap? 😅
D72, Out rectifier, only one that starts to generate heat. The rest of the FETs stay dead cold.
Can’t wait to finally get a thermal imaging cam, anyone selling one cheap? 😅