Another to go is a LM4780 module that I got from the EU. It's the module only with no heatsink, case etc and pics with these are only for reference. Sounds OK but nothing flash. DC offset was less than 6mV for each channel.
The crappy electrolytic caps were changed to Nichicon FW for the power supply and FG for the feedback. The chip had been installed back from the edge of the PCB which meant the chip could not sit flat on the heatsink. It was installed so the PCB went under the heatsink which was mounted on spacers but a metal spacer on the heatsink would also work.
Power supply to be no more than 18-0-18 transformer to give ±25VDC rails as the caps are 35V rated. With this supply expect 29W into 8R, 41W into 6R and 57W into 4R. Heatsink should be better than 1°C/W.
I don't recommend running it in parallel as it didn't like it even though the feedback resistors have 0.1% tolerance. The same would also apply to bridged mode.
These are tricky to mount as the mounting screws can go off on angle but I will supply the spreader that sits on the chip face as well as the insulated mounting screws which as required as these can touch metal in the mounting holes. It's essential that the chip be isolated from the heatsink and I'm supplying the used silicone pad. I'll also supply the input wiring and connector.
I couldn't find anything on this module but did find a pic of the PCB which is attached.
I'll cover the postage in Australia and again this is for the module, spreader, screws, insulator and input wires only.
The crappy electrolytic caps were changed to Nichicon FW for the power supply and FG for the feedback. The chip had been installed back from the edge of the PCB which meant the chip could not sit flat on the heatsink. It was installed so the PCB went under the heatsink which was mounted on spacers but a metal spacer on the heatsink would also work.
Power supply to be no more than 18-0-18 transformer to give ±25VDC rails as the caps are 35V rated. With this supply expect 29W into 8R, 41W into 6R and 57W into 4R. Heatsink should be better than 1°C/W.
I don't recommend running it in parallel as it didn't like it even though the feedback resistors have 0.1% tolerance. The same would also apply to bridged mode.
These are tricky to mount as the mounting screws can go off on angle but I will supply the spreader that sits on the chip face as well as the insulated mounting screws which as required as these can touch metal in the mounting holes. It's essential that the chip be isolated from the heatsink and I'm supplying the used silicone pad. I'll also supply the input wiring and connector.
I couldn't find anything on this module but did find a pic of the PCB which is attached.
I'll cover the postage in Australia and again this is for the module, spreader, screws, insulator and input wires only.
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