资 源 简 介
The RT9246 is a mulTI-phase buck DC/DC controllerintegrated with all control funcTIons for GHz CPU VRM.The RT9246 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.RT9246 controls both voltage and current loops to achievegood regulation, response & power stage thermal balance.Precise current loop using RDS(ON) as sense componentbuilds precise load line for strict VRM DC & transientspecification and also ensures thermal balance of differentpower stages. The settings of current sense, droop tuning,VCORE initial offset and over current protection areindependent to compensation circuit of voltage loop. Thefeature greatly facilitates the flexibility of CPU power supplydesign and tuning.The DAC output of RT9246 supports K8 CPU by 5-bit VIDinput, precise initial value & smooth VCORE transient atVID 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.
