Micro Linear ML4890
The ML4890 is a high efficiency, PFM (Pulse Frequency Modulation), boost switching regulator connected in series with an integrated LDO (Low Dropout Regulator) that incorporates “Silent Switcher™” technology. This technique incorporates a patented tracking scheme to minimize the voltage drop across the LDO and increase the total efficiency of the regulator beyond that which can be obtained by using a discrete external LDO regulator. The ML4890 is designed to convert single or multiple cell battery inputs to regulated output voltages for integrated circuits and is ideal for portable communications equipment that cannot tolerate the output voltage ripple normally associated with switching regulators.