I am using a linear regulator ([MIC29302WU](https://www.digikey.com/product-detail/en/microchip-technology/MIC29302WU/576-3369-5-ND/1029125)) to power a computer mounted inside my car. There is significant noise being passed along the ground of the regulator to the main computer. I verified this by connecting an inverter to the battery and using a 12 V power supply which eliminated the noise.

Can anyone suggest an isolation circuit? I would like to consider cost and board area. Would this require a flyback design? Or can I get away with not using a transformer?