Patent ID: 8373398
Filing Date: 2013-02-12
Classification: G05F

Abstract:
1. A voltage regulator to provide an output voltage at an output port in response to an input voltage at an input port, comprising: first and second transistors having first current terminals coupled together to form said input port and having second current terminals coupled together to form said output port wherein said first transistor has a first breakdown voltage and said second transistor has a second breakdown voltage that exceeds said first breakdown voltage; a voltage divider coupled to said second current terminals to provide a divided voltage less than said output voltage; a differential amplifier coupled to drive a control terminal of said first transistor in response to the difference between said divided voltage and a reference voltage; and a comparator coupled to enable said differential amplifier and disable said second transistor when the difference between said input voltage and said output voltage is less than a predetermined voltage; reduction of die area of said voltage regulator thereby facilitated because operational voltage across said first transistor restricted to less than said predetermined voltage and because said second transistor disabled after said difference is less than said predetermined voltage.