Build Thread for TPA BIII + Ian Async I2S FIFO + OPC NTD1 + Salas SSLV

[bigpandahk]

After installed Ian's isolator board, the bass become much clear and powerful. I am waiting for the i8605 for the additional isolation on the I2C bus.
Today, receive the battery management board and will assemble it ASAP.
Unfortunately, my DAC has a new problem, actually it should be old issue but happen more frequent. When I used the Legato for couple of days, I found its temperature is abnormally high. Some resistors reach 75 deg. C after 20-30 minutes operation. I have raised this query in the TPA support forum but was told it is normal.
Now, I believe the high temperature already damage some component(s). Last month the Legato start to fail after couple hours, but now it can only survive for several minutes.
Both channels have no sound when fail, any suggestion to trace the problem? Please!!

[iancanada]

Originally Posted by bigpandahk

After installed Ian's isolator board, the bass become much clear and powerful. I am waiting for the i8605 for the additional isolation on the I2C bus.
Today, receive the battery management board and will assemble it ASAP.
Unfortunately, my DAC has a new problem, actually it should be old issue but happen more frequent. When I used the Legato for couple of days, I found its temperature is abnormally high. Some resistors reach 75 deg. C after 20-30 minutes operation. I have raised this query in the TPA support forum but was told it is normal.
Now, I believe the high temperature already damage some component(s). Last month the Legato start to fail after couple hours, but now it can only survive for several minutes.
Both channels have no sound when fail, any suggestion to trace the problem? Please!!

Please go through the schematics of the battery board before assemble. Too many options for a simple board. As well as the isolator board. I'm afraid you may need the pull-up resistors for the I2C buses if they were not included on both DAC and controller side.

Ian

[qusp]

solution, use a proper IV stage =P not long to wait now

[gomer96]

Hello bigpandahk,
I just grabbed my cheap rigdgid 'microray' IR temp reader and I'm looking at close to the same as you. I'm getting ~155-165 degrees F
which on the higher side ends up very close to your 75C reading.
I 'shot' the resistors along VR1+2 on both of my legatos. One was about 10-15 degrees warmer. I'm feeding these ~14.8 volts from the
placid BP supplies. So far, they still play and sound WONDERFUL.
Just for kicks I 'shot' my placid heatsinks, which are the taller ones on Leon's BOM and they were around 140-150F.

sorry for not much help. I'm still wrestling with my arduino control.

/mike

[glt]

those resistors are too close to each other so they warm each other up. One solution was to put the middle one on the bottom of the board... and to elevate them away from the board so they get more air through... (I have not built mine yet so it is all head knowledge :-))

[bigpandahk]

Originally Posted by iancanada

Please go through the schematics of the battery board before assemble. Too many options for a simple board. As well as the isolator board. I'm afraid you may need the pull-up resistors for the I2C buses if they were not included on both DAC and controller side.

Ian

Ian

Thanks for your advice.

[bigpandahk]

Originally Posted by qusp

solution, use a proper IV stage =P not long to wait now

Of course and my future is in your hand

[bigpandahk]

Originally Posted by gomer96

Hello bigpandahk,
I just grabbed my cheap rigdgid 'microray' IR temp reader and I'm looking at close to the same as you. I'm getting ~155-165 degrees F
which on the higher side ends up very close to your 75C reading.
I 'shot' the resistors along VR1+2 on both of my legatos. One was about 10-15 degrees warmer. I'm feeding these ~14.8 volts from the
placid BP supplies. So far, they still play and sound WONDERFUL.
Just for kicks I 'shot' my placid heatsinks, which are the taller ones on Leon's BOM and they were around 140-150F.

sorry for not much help. I'm still wrestling with my arduino control.

/mike

Thanks for the information. At least confirm the high temperature is comment to Legato, not any assemble problem that I had made.

[bigpandahk]

Originally Posted by glt

those resistors are too close to each other so they warm each other up. One solution was to put the middle one on the bottom of the board... and to elevate them away from the board so they get more air through... (I have not built mine yet so it is all head knowledge :-))

I have to find out the faulty component first and will implement your suggestion. Thanks glt.

[gomer96]

Originally Posted by glt

those resistors are too close to each other so they warm each other up. One solution was to put the middle one on the bottom of the board... and to elevate them away from the board so they get more air through... (I have not built mine yet so it is all head knowledge :-))

Yes glt, if I were to build one new I'd do that and/or space them off the board for some air flow.

If you haven't started your build yet, I'd
highly recommend stacking boards where you can, ie
input board, sidecar, etc. Saves space besides the extra
wire.

/mike