The HIP6501A, paired with either the HIP6020 or HIP6021, simplifies the implementation of ACPI-compliant designs in microprocessor and computer applications. The IC integrates two linear controllers and a low-current pass transistor, as well as the monitoring and control functions into a 16-pin SOIC package. One linear controller generates the 3.3VDUAL voltage plane from an ATX power supply's 5VSB output during sleep states (S3, S4/S5), powering the PCI slots through an external pass transistor, as instructed by the status of the 3.3VDUAL enable pin. An additional pass transistor is used to switch in the ATX 3.3V output for PCI operation during S0 and S1 (active) operatingstates. The second linear controller supplies the computer system's 2.5V/3.3V memory power through an external pass transistor in active states. During S3 state, an integrated pass transistor supplies the 2.5V/3.3V sleep-state power. A third controller powers up a 5VDUAL plane by switching in the ATX 5V output in active states, or the ATX 5VSB in sleep states.