Patent ID: 7710195

Claim:
A voltage boost circuit for boosting a supply voltage, the voltage boost circuit comprising: a first stage for boosting the supply voltage to a first boosted voltage, the first stage including a first voltage boost capacitor with a low node and a high node, the high node having an output of the first boosted voltage; a first passgate coupled to the high node of the first stage; a first gate control circuit for generating an on-state gate voltage level for the first passgate adjusted to reduce gate oxide voltage stress on the first pass-gate; a second stage for boosting the first boosted voltage to a second boosted voltage, the second stage including a second voltage boost capacitor with a low node coupled to the first passgate, and a high node; a second passgate coupled to the high node of the second stage for transferring the second boosted voltage to an output node; a second gate control circuit for generating an on-state gate voltage level for the second passgate adjusted to reduce gate oxide voltage stress on the second passgate; and a precharge circuit for coupling the high node of the second stage to a gate node of a precharge transistor thereof for disabling the precharge transistor and preventing leakage back to the supply voltage, the precharge circuit including a stack of transistors configured to prevent voltage stress on a transistor of the second passgate during a precharge phase of operation.