资 源 简 介
The RT9246A is a mulTI-phase buck DC/DC controllerintegrated with all control funcTIons for GHz CPU VRM.The RT9246A controls 2 or 3 buck switching stagesoperaTIng in interleaved phase set automaTIcally. The multiphasearchitecture provides high output current whilemaintaining low power dissipation on power devices andlow stress on input and output capacitors. The highequivalent operating frequency also reduces thecomponent dimension and the output voltage ripple in loadtransient.RT9246A controls both voltage and current loops to achievegood regulation, response & power stage thermal balance.Precise current loop using Inductor DCR as sensecomponent builds precise load line for strict VRM DC &transient specification and also ensures thermal balanceof different power stages. The settings of current sense,droop tuning, VCORE initial offset and over current protectionare independent to compensation circuit of voltage loop.The feature greatly facilitates the flexibility of CPU powersupply design and tuning.The DAC output of RT9246A supports K8 CPU by 5-bitVID input, precise initial value & smooth VCORE transientat VID jump. The IC monitors the VCORE voltage for PGOODand over-voltage protection. Soft-start, over-currentprotection and programmable under-voltage lockout arealso provided to assure the safety of microprocessor andpower system.
