car PSU

I am building a Haynes Roadster car and want to be able to do sequences with the rear LED lights when at shows etc. I am happy programming an arduino, however, i’m no electronics expert. I am needing some advice on where to buy a reliable PSU to power an arduino from noisy car electrics. As I need a level of integrity, is there any arduino that is more robust than others?. I will be switching LED lights with relatively low current <500mA - would rather switched with transistors rather than relays as would like a strobe effect and don’t think relays will switch quick enough. Again any advice on a off the shelf module (10 output) that could achieve this?

(ill be building in a bypass so lights will function as normal on the road)

Any advice much appreciated.

A ULN2803A has eight transistors in one package. The output can switch up to 500mA. There is a limitation on the total package current, 2.5 amp maximum, so 0.3 amps maximum on each with all eight on. The transistor voltage rating is 50 volts.

For higher current I found this. Only for outputs but the output terminal connections would be easier to use.

I think this would work well to connect to the above modules. UNO Shield / Nano Shield for NANO 3.0 and UNO R3 duemilanove Expansion board|module i2c|arduino sensor shieldshield arduino - AliExpress

Use this as a power supply for the arduino. LM2596HVS LM2596 HV LM2596HV DC DC Adjustable Step Down Buck Converter Power Module 4.5 50V To 3 35V Urrent limiting|power module|buck converterstep down dc-dc - AliExpress
The important thing here is the high input voltage capability. Yes the electrical system is a nominal 12 volts but there is a lot of high voltage noise that can be present. I would have prefered a module with terminal blocks for you but the voltage consideration is more important.

Put a diode in series with the positive input of the supply. Any general purpose diode, like a 1N4004. That should give some protection from negative voltages.

craigdiver:
As I need a level of integrity, is there any arduino that is more robust than others?

Ruggeduino

That is fantastic info guys, thank you

Rudy216:
A ULN2803A has eight transistors in one package. The output can switch up to 500mA. There is a limitation on the total package current, 2.5 amp maximum, so 0.3 amps maximum on each with all eight on.

You forgot about the thermal limitation.
At 2.5Amp, the chip could be 250 degrees C.
Leo..