This is a really simple question...
What is the best way to ensure that voltage spikes don't kill my iPod or satnav when used on a home brew 12v to 5v dropper in my cars..
zener, VDR's, chokes or a combination of all three? Or maybe something I aint thought of..!
I am looking to get rid of all the shyte on the +12v supply before it goes to the regulator..
I had a DSO on the +12v lines on my cars, and saw spikes of well over 200v!
All those motors, injectors and relays turning on and off, with no snubber networks or diodes.. OUCH....
Designed primarily to survive in the harsh automotive environment, these devices will protect all external load circuitry from input faultconditions caused by reverse battery connection, two battery jump starts, and excessive line transients during load dump. This series also includes internal current limiting, thermal shutdown, and additionally, is able to withstand temporary power−up with mirror−image insertion.
I'd say a choke and zeners. The choke is probably the cheapest/simplest to use, especially for spikes. They can be as simple as snapping the choke onto the cable, if no data is being transmitted looping the cable multiple times through the choke increases it's effectiveness dramatically. See what you read from a common RF choke with multiple turns of the input wire through it. Large inductor values are the simplest thing you can use to decrease the voltage from other inductive 'discharges' in the system.
I am looking to get rid of all the shyte on the +12v supply before it goes to the regulator..
I had a DSO on the +12v lines on my cars, and saw spikes of well over 200v!
All those motors, injectors and relays turning on and off, with no snubber networks or diodes.. OUCH....
A choke and a 20V zener on the input of the regulator will do the job. The regulator should remove the rest of the crap and provide adequate protection for your iPod.