1966

 

That would also work well Bill. I'm being cheap.

 

Glyn
Diodes are also very cheap. Mostly sold in a pack of 10 ranging from 2 to 5 dollars a pack depending on amperage rating.
I would use a 5-amp diode which should be more than capable of passing the drain on the system.

 

The only reaason I like pico fuses, other than price, is that it is so easy to check if they are blown. But diodes are pretty easy to check as well to be fair as long as they blow infinite current.

 

The purposes are slightly different (I think). A capacitor or diode across the input (and possibly output) of the IC filters off voltage spikes. A fuse on the live output protects against shorts to ground. On the live input, it would protect against current surges. Personally, I'd settle for a pair of ceramic capacitors (in series) across the input. On the output side, it depends on the sensitivity of the IC to shorts. At some point, it costs no more to replace the IC than whatever is protecting it. In fact, the cost is the time and inconvenience.