This part is a kind of semiconductor called APW7058.

Function of this product has Synchronous Buck PWM and Linear Controllers.

Manufacturers : Anpec Electronics Coropration

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APW7058 Synchronous Buck PWM and Linear Controllers Features • Provides Two Regulated Voltages - One Synchronous-Rectified Buck PWM Controller - One Linear Controller General Description The APW7058 integrates one synchronous-rectified Buck PWM controller and one linear controller to provide two regulated voltages for graphics cards and other embedded processor applications. The PWM controller which drives dual N-channel MOSFETs uses fixed 600kHz frequency, voltage-mode PWM control and integrates power-on-reset(POR), built-in soft-start, output under-voltage monitoring and shutdown functions into a single chip. The linear controller which drives a N-channel MOSFET bypass transistor allows users to optimize the transient response by external components. The POR circu [ ... ]

APW7058 PDF Datasheet Download