Nifty heat sink

The fans will eventually collect lint and block the airflow. See

Bring out your dead: Reg readers reveal filthy, filthy PCs:

Eliminate the fans. Go class D:

What are the Different Types of Audio Amplifier Classes?

and

Amplifier Classes from A to H

I considered those recently, but they looked mechanically fragile on a PC board.

I went with individual heat sinks, which we had in stock anyhow.

which have the advantage of not needing insulators.

These will go on a PCB with a fan mounted on the board too, blowing directly on four big fets in an h-bridge.

John, your point about mechanical stability is well taken. I would definit ely hesitate to use these in singles. In pairs, with a fan bolted on, they 're solid as a rock, but on my board, the two heatsinks without a fan are p retty floppy. I think I'll bolt a fan guard onto those two, to stabilize t hem. This application put an emphasis on compactness and the ability to du ct the heat away from the experiment, so this heatsink system is a natural.

Steve, this board is four amplifiers, bridge driven 40Vpp at 1A, DC to 10 M Hz, so class D is not an option.

-Jim

Are you aware of the The Royal Society of L The Royal Society's motto 'Nullius in verba' is taken to mean 'take nobody's word for it'. It is an expression of the determination of Fellows to withstand the domination of authority and to verify all statements by an appeal to facts determined by experiment.

They plainly think "trust" has nothing to do with it!

Just got a solder-sample board and checked the heat sink mounting.

Looks good, nice and rigid. There will be four of them, on the bottom side, with a fan on the board just to the right.