Start-up circuit for voltage regulator with current foldback

A vehicle controller comprising:

• at least one sub-controller;
• a power supply, said power supply powering said at least one subcontroller, said power supply including:
• a first voltage source, said first voltage source providing a first supply voltage;
• a first linear voltage regulator, said first linear voltage regulator receiving said first supply voltage and generating a second supply voltage, said second supply voltage being less than said first supply voltage;
• a power up assist circuit including:
• a first circuit loop, said first circuit loop having a first voltage output;
• and
• a second circuit loop, said second circuit loop having a second voltage output such that during an initial power up stage said first circuit loop supplies said second voltage output, said second voltage output being assisted by said first voltage output through said first circuit loop and said second circuit loop causing deactivation of said first circuit loop after said second voltage output achieves a predetermined value such that said first circuit loop no longer supplies said second voltage output.

A multi-voltage power supply, comprising:

• a first voltage source, said first voltage source providing a first supply voltage;
• a first linear voltage regulator receiving said first voltage as input, said first linear voltage regulator providing a second voltage, said second voltage being less than said first voltage;
• and
• a power up assist circuit positioned between outputs of said first power supply and said first linear voltage regulator, said power up assist circuit supplementing said second voltage during a power up mode.