Questions about automotive supply (ignition moment)

[one]

automotive supply

Hi

I need an supply for 12 and 24 v , begin whit Switch regular of on semi
mc34166, i have a cuestion
how protect my circuit of ignition moment, in this transient the supply of car have peek 0v ~ vcc+40% , in this moment i lose my data in ram.


thanks for u comments!

 

[flatulent]

two methods combined

You will have to use two methods at the same time, filter and clip. The filtering will be like a low pass filter using inductors and capacitors on the input of the switching regulator. Then you have to use clipping devices such as MOV or zener diodes.

 

[Analyzer]

Hi,
Try to squeeze AC in supply voltage with an inductor or capacitors.You can use voltage rectifiers or instant regulators.

Analyzer.

 

[Sebi]

Apply a high capacity condenser and a serial schottky diode.