Abstract: An eight-transistor tri-state driver. The tri-state driver implements multiple cascade structures where each cascade structure may refer to a pair of complementary transistors serially connected. Each cascade structure may include a p-conductivity type transistor serially connected to a n-conductivity type transistor. By implementing cascade structures in a tri-state driver, there is a lower peak current consumption, a reduced slew rate as well as a reduction in the amount of layout area used in comparison to the classic tri-state drivers.

Abstract: A mixed signal processing system (22) includes digital (28) and analog (29) systems and is powered by a variable external voltage, such as a battery voltage. A voltage regulator (41) regulates the battery voltage to a nominal potential less than the battery voltage. The voltage regulator (41) provides the regulated voltage to a digital subsystem (51) of the digital system (28). A regulated charge pump (43) provides a voltage which is above the battery voltage and substantially constant due to regulation. The regulated charge pump (43) provides the regulated charge-pumped voltage to an analog subsystem (61) of the analog system (29) for better analog operation. A level shifter (44) equalizes signal levels between the digital (28) and analog (29) systems.