SS7529 Datasheet | Silicon Standard

Synchronous Buck PWM and Linear Power Controller FEATURE Controller operates from 5V and 12V Drives two N-channel MOSFETs for switching buck converter Drives an N-channel MOSFET on the linear output Fixed 600k Hz constant switching frequency Full range 0~100% duty cycle Internal soft start Fast transient response UVP monitoring on both outputs Internal 0.8V reference voltage. GENERAL DESCRIPTION The SS7529 consists of a dual-output power controller and the protection circuits in a single SO-14 package for graphic cards and other applications. The dual-output power controller provides regulation by driving two N-MOSFETs in a synchronous rectified buck converter, and one N-MOSFET in a linear configuration. The synchronous rectified buck converter provides simple, single feedback loop, voltage mode control with fast transient response, from an internal 0.8V temperaturepensated reference voltage. A fixed 600k Hz frequency oscillator reduces design plexity, while balancing typical application cost and efficiency. The internal soft-start function and the 12V direct drive on the switching output help to save the bootstrap circuit. Furthermore, the internal POR (power on reset) helps to prevent the system from sequencing issues during the startup and turn-off. Reacting to fault conditions, the SS7529 will shutdown both outputs when the voltage on either FB or FB2 pins drops below 51% of their nominal value. APPLICATIONS Graphics-GPU and memory supplies ASIC power supplies Embedded processor and I/O supplies Cable Modem, Set Top Box, and DSL Modems DSP and Core munications Processor supplies TYPICAL APPLICATIONS Vin (3.3V or 5V) .Data Sheet.net/ 5V 12V Q3 5VCC 12VCC DRIVE2 FB2 Linear Controller Control Logic Shutdown Vout Vref UGATE Q1 Error Amp FB p Vout LGATE Q2 PGND Rev.1.01 4/26/2004 .Silicon...