I'm fairly certain that this is not actually a PG amp, but something with a PG badge. The board is very generic looking and only has a model number, no company etc.
I have 4 of these amps in from a customer, and the one I'm looking at pops in/out of protect about once every 3 seconds. I measured briefly +-73vDC rail, and also measured 2.4vDC across speaker terminals which is why its probably going into protect. I find no shorted outputs.
These are going to be interesting. The board on top is fairly simple, but underneath is all SMD, so its impossible to test out of the sync unless I construct a jig of sort.
Is this one of the general class D amps I can brief through the DVD?
Photo coming.
I have 4 of these amps in from a customer, and the one I'm looking at pops in/out of protect about once every 3 seconds. I measured briefly +-73vDC rail, and also measured 2.4vDC across speaker terminals which is why its probably going into protect. I find no shorted outputs.
These are going to be interesting. The board on top is fairly simple, but underneath is all SMD, so its impossible to test out of the sync unless I construct a jig of sort.
Is this one of the general class D amps I can brief through the DVD?
Photo coming.
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I'd need to see the components clustered near the output stage well enough to read the values/part numbers to see if it's familiar.
1" x 3/8" aluminum bar stock insulated with Kapton tape is all you need to protect the semiconductors. Clamp the transistors to it with binder clips. See attached.
1" x 3/8" aluminum bar stock insulated with Kapton tape is all you need to protect the semiconductors. Clamp the transistors to it with binder clips. See attached.
Attachments
I put in place a temporary 4-ohm 2w resistor and it blew open within seconds without excessive current draw, and amp still flipping into protect every 3 seconds again. Amp still pulsing 2.4vDC across speaker terminals.
I have a few exact amps here for reference.
The first amp as you pointed out, had all 4x 16ohm resistors blown open. I could not read their values so I referred to a second amp I have here and also posted a photo of that second amp.
On the first amp with a problem I removed the blown open R155-158, and subbed a 2w 4ohm resistor temporarily, which blew open just like the original SMD parts.
The first amp as you pointed out, had all 4x 16ohm resistors blown open. I could not read their values so I referred to a second amp I have here and also posted a photo of that second amp.
On the first amp with a problem I removed the blown open R155-158, and subbed a 2w 4ohm resistor temporarily, which blew open just like the original SMD parts.
I pulled the output transistors of off the bad amp The amp appears to be powering up and staying powered as such. I'm going to compare driverIC voltages between this and another working amp and post later today.
The output PWM this amp is using is an IRS20957S.
Referencing negative speaker terminal
On a working RX2-1000.1, I'm getting the following voltages:
IRS20957S
1: 10.32
2: 0
3: 2.5
4: 0
5: 0
6: -54.5
7: -57.2
8: -56.2
9: -59.6
10: -53.6
11: -47.6
12: 0
13: 0
14: 4.87
15: 11.25
16: 1.06
On this amp which is not working correctly, I'm getting the following; with output transistors removed:
IRS20957S
1: 10.29
2: 0.6 ~ 0.7 variable
3: 0.152
4: 0
5: 0
6: -74.8
7: -79
8: -77
9: -80.7
10: -80.8
11: -68.9
12: 0
13: 1.738
14: 1.738
15: 17.10
16: 1.738
So I bolded a few numbers from the bad amp.
Pin 13 is connected to the 2045 pin 3 About 2~5 ohms resistance to Pin 2
Pin 14 is connected to the 2045 pin 2 About 2~5 ohms resistance to Pin 3
Pin 16 is connected to the 2045 pin 5, but through 2 resistors in series
Its also strange that the rail voltage is higher on the non-working amp.
Datasheets:
20957S:
https://www.mouser.com/datasheet/2/196/Infineon-IRS20957SPBF-DS-v01_02-EN-1732020.pdf
2045
https://www.mouser.com/datasheet/2/115/ZXTC2045E6-75108.pdf
I'm going to remove the 2045 as thats a bit easier at this point and likely checkable out of circuit.
Referencing negative speaker terminal
On a working RX2-1000.1, I'm getting the following voltages:
IRS20957S
1: 10.32
2: 0
3: 2.5
4: 0
5: 0
6: -54.5
7: -57.2
8: -56.2
9: -59.6
10: -53.6
11: -47.6
12: 0
13: 0
14: 4.87
15: 11.25
16: 1.06
On this amp which is not working correctly, I'm getting the following; with output transistors removed:
IRS20957S
1: 10.29
2: 0.6 ~ 0.7 variable
3: 0.152
4: 0
5: 0
6: -74.8
7: -79
8: -77
9: -80.7
10: -80.8
11: -68.9
12: 0
13: 1.738
14: 1.738
15: 17.10
16: 1.738
So I bolded a few numbers from the bad amp.
Pin 13 is connected to the 2045 pin 3 About 2~5 ohms resistance to Pin 2
Pin 14 is connected to the 2045 pin 2 About 2~5 ohms resistance to Pin 3
Pin 16 is connected to the 2045 pin 5, but through 2 resistors in series
Its also strange that the rail voltage is higher on the non-working amp.
Datasheets:
20957S:
https://www.mouser.com/datasheet/2/196/Infineon-IRS20957SPBF-DS-v01_02-EN-1732020.pdf
2045
https://www.mouser.com/datasheet/2/115/ZXTC2045E6-75108.pdf
I'm going to remove the 2045 as thats a bit easier at this point and likely checkable out of circuit.