The ML6554 switching regulator is designed to convert voltage supplies ranging from 2.3V to 4V into a desired output voltage or termination voltage for various applications. The ML6554 can be implemented to produce regulated output voltages in two different modes. In the default mode, when the VREF pin is open, the ML6554 output voltage is 50% of the voltage applied to VCCQ. The ML6554 can also be used to produce various user-defined voltages by forcing a voltage on the VREFIN pin. In this case, the output voltage follows the input VREFIN voltage. The switching regulator is capable of sourcing or sinking up to 3A of current while regulating an output VTT voltage to within 3% or less. The ML6554, used in conjunction with series termination resisitors, provides an excellent voltage source for active termination schemes of high speed transmission lines as those seen in high speed memory buses and distributed backplane designs. The voltage output of the regulator can be used as a termination voltage for other bus interface standards such as DDR SDRAM, SSTL, CMOS, RambusTM, GTL+, VME, LV-CMOS, LV-TTL, HSTL and PECL.