Patent ID: 6700407
Filing Date: 2004-03-02
Classification: H03K

Abstract:
An extended voltage range level shifter, comprising:an input inverter comprising thin-gate devices, the input inverter coupled to an internal power supply associated with an internal voltage domain and operable to receive internal data in the internal voltage domain and to generate inverted internal data; a first circuit branch comprising A) a p-type, thick-gate transistor having a source coupled to an external power supply associated with an external voltage domain, B) a first n-type, thick-gate transistor having a drain coupled to a drain of the p-type transistor and a gate operable to receive a reference voltage, the reference voltage less than the external power supply and greater than the internal power supply, and C) a second n-type, thin-gate transistor having a source coupled to ground, a drain coupled to a source of the first n-type transistor, and a gate operable to receive the internal data; and a second circuit branch comprising A) a p-type, thick-gate transistor having a source coupled to the external power supply, a drain coupled to a gate of the p-type transistor for the first circuit branch, and a gate coupled to the drain of the p-type transistor for the first circuit branch, B) a first n-type, thick-gate transistor having a drain coupled to a drain of the p-type transistor and a gate operable to receive the reference voltage, and C) a second n-type, thin-gate transistor having a source coupled to ground, a drain coupled to a source of the first n-type transistor, and a gate operable to receive the inverted internal data.