Description

The SC2446 is a high-frequency dual synchronous stepdown switching power supply controller. It provides outof-phase high-current output gate drives to all N-channel MOSFET power stages. The SC2446 operates in synchronous continuous-conduction mode. Both phases are capable of maintaining regulation with sourcing or sinking load currents, making the SC2446 suitable for generating both VDDQ and the tracking VTT for DDR applications.

Features

◆ 2-Phase synchronous continuous conduction mode for high efficiency step-down converters

◆ Out of phase operation for low input current ripples

◆ Output source and sink currents

◆ Fixed frequency peak current-mode control

◆ 75mV/-110mV maximum current sense voltage

◆ Synthesized MOSFET R DS(ON) current-sensing for low-cost applications

◆ Optional resistor current-sensing for precise currentlimit

◆ Dual outputs or 2-phase single output operation

◆ Excellent current sharing between individual phases

◆ Wide input voltage range: 4.7V to 16V

◆ Individual soft-start, overload shutdown and enable

◆ Duty cycle up to 88

◆ 0.5V feedback voltage for low-voltage outputs

◆ External reference input for DDR applications

◆ Buffered V DDQ/2 output

◆ Programmable frequency up to 1 MHz per phase

◆ External synchronization

◆ Industrial temperature range

◆ 28-lead TSSOP - EDP package

Applications

◆ Telecommunication power supplies

◆ DDR memory power supplies

◆ Graphic power supplies

◆ Servers and base stations