I'm designing a power amplifier using the LM1875, and taking the design straight from the TI datasheet: https://www.ti.com/lit/ds/symlink/lm1875.pdf
What heatsink can I use for this? I will be using a 3A 20V DC adapter to power this. A specific model number for the heatsink would be greatly appreciated! Thank you!
What heatsink can I use for this? I will be using a 3A 20V DC adapter to power this. A specific model number for the heatsink would be greatly appreciated! Thank you!
Well no such thing as a heatsink
that is too big.
But dont exactly need 100 watt sink.
but is always fun.
Just check ebay for whatever monster
or average heatsink you can mount
the thing too.
buy a blank/ or drilled and drill / tap where ever you
want.
that is too big.
But dont exactly need 100 watt sink.
but is always fun.
Just check ebay for whatever monster
or average heatsink you can mount
the thing too.
buy a blank/ or drilled and drill / tap where ever you
want.
For a 20 volt single supply? A piece of 1x1 inch angle aluminum, about 5 inches long. Dissipation will be 5 to 6 watts.
You get ready drilled tapped heat sink kits with insulating washer, screws etc. here for about 50 cents.
Buy them from the same supplier as the chip, save some shipping.
Actually, you can get pretty creative in heat sinks, but above suggestion is enough.
It looks like a laptop supply, add 100 nF, 470 pF in the inputs, and try to ground them all together, supply and board, as a noise filter.
Buy them from the same supplier as the chip, save some shipping.
Actually, you can get pretty creative in heat sinks, but above suggestion is enough.
It looks like a laptop supply, add 100 nF, 470 pF in the inputs, and try to ground them all together, supply and board, as a noise filter.
You can use old AMD CPU heatsink , just cut, drill (tap or no tap) , use a long screw and power up the CPU fan with voltages from 5 to 12V. Since this is singe supply design , the tab is Gnd, so isolation washers are optional. You can also salvage pre-tapped heatsinks from old PC SMPS with screws. I can post pics if you want to see my implementation. 4 Ohms speakers demand better heatsink vs 8 Ohms load. Use adaptor with earthing (3-pin plug)
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Note that the space between the fins Is small when used with fan, and large when used with Natural convection. Heathsinks allow tò work passively