Patent ID: 7808300

Claim:
A high voltage generator comprising: a voltage generator configured to produce a regulated high voltage supply in response to a control signal; a voltage clamp comprising a plurality of reverse biased zener diodes connected in series with a plurality of forward biased zener diodes configured to limit a magnitude of said regulated high voltage supply and produce a clamp current that is determined only by the regulated high voltage supply applied to the voltage clamp; and a power regulator, comprising: a mirror voltage transistor configured to produce a mirror voltage reflecting a magnitude of said clamp current; a current limit transistor configured to produce a limit current; and a current mirror transistor configured to receive said mirror voltage, to generate a mirror current in response to said clamp current, said mirror current being constrained by said limit current, and to produce a control voltage; said power regulator configured to produce said control signal to change when the mirror current equals the limit current and the clamp current is increasing to terminate the production of the regulated high voltage supply.