Abstract: An integrated circuit (40) has a low-power mode in which at least one switched inverter stage (60) of a clock amplifier (41) is disabled in response to a stop signal. The stop signal indicates that the integrated circuit (40) is in low-power mode. In one embodiment, each switched inverter stage is a complementary metal-oxide-semiconductor (CMOS) switched inverter (60), in which an additional P-channel transistor (61) is connected between the source of an inverter P-channel transistor (62) and a positive power supply voltage terminal, and in which an additional N-channel transistor (64) is connected between a source of an inverter N-channel transistor (63) and a negative power supply voltage terminal. A non-switched inverter stage (52) remains active during low-power mode to maintain a DC value of a clock input signal near a switchpoint of the clock amplifier (41).

Abstract: A data processing system (10) has programmable normal and low voltage modes of operation. The normal voltage mode of operation enables precharge transistors (32, 34) to couple a voltage of (V.sub.DD -V.sub.tn) to each of a plurality of precharge circuit nodes, such as precharge bus (30), within data processing system (10). During the low voltage mode of operation, the full V.sub.DD is coupled to each precharge circuit node, wherein the power supply voltage during the low voltage mode of operation is reduced. Data processing system (10) has a voltage mode bit (36) for receiving voltage mode information from a source external to data processing system (10). In response to an active logic state within voltage mode bit (36), a low voltage mode clocking circuit (42) is enabled.