Patent ID: 8680912

Claim:
Level shifting circuitry for generating an output signal in response to an input signal, said input signal having one of a lower input voltage level and a higher input voltage level, and said output signal having one of a lower output voltage level and a higher output voltage level; said level shifting circuitry comprising: a pulldown path configured to pull said output signal to said lower output voltage level in response to a first transition of said input signal, said first transition comprising one of a rising transition from said lower input voltage level to said higher input voltage level and a falling transition from said higher input voltage level to said lower input voltage level; a pullup path configured to pull said output signal to said higher output voltage level in response to a second transition of said input signal, said second transition comprising the other of said rising transition and said falling transition of said input signal; pullup control circuitry configured to place said pullup path in a non-conductive state in response to said pullup path pulling said output signal to said higher output voltage level; and a keeper path configured to keep said output signal at said higher output voltage level while said pullup path is in said non-conductive state until said pulldown path pulls said output signal to said lower output voltage level; wherein a maximum drive current of said pulldown path is greater than a maximum drive current of said keeper path.