Bi-Phase Buck Controller Sports Two LDOs

Raising the integration bar, the AQ9220 dual-phase, synchronous buck controller features two LDO controllers. One is capable of driving an external n-channel MOSFET for VDDQ, while the second drives two external n-channel MOSFETs to supply current sourcing and sinking for the VTT termination voltage required by DDR memory. The device also includes a five-bit VID interface with adjustable step and offset voltages. To minimize power loss and noise, the PWMs are operated 180° out of phase. Other features include constant on-time regulation, lossless inductor current sensing, active phase current sharing with adjustable ratio, and over-current protection. Available in either an MLP-40 or LQFP-44, price is $1.20 each/1,000. ARQUES TECHNOLOGY INC., Santa Clara, CA. (408) 969-0868.