SC2441A Datasheet Text
1.8V to 20V Input 2-Phase Synchronous .. Step-down Controllers with Step-up Converter
POWER MANAGEMENT Description
The SC2441A is a programmable frequency dual independent or dual/multiple phase single output peak current-mode step-down switching regulator controller. It is capable of operating from 1.8V to 20V input. A 0.6A step-up converter in the SC2441A generates an auxiliary gate drive supply when VIN is below 4.5V. This makes the SC2441A well suited for applications where a low-voltage input (<3.3V) is to be stepped down for lower voltage logic, yet the input is too low to drive power MOSFETs efficiently. The SC2441A employs a phase-locked synchronizing circuit that allows the step-up converter to operate at twice the switching frequency of the step-down controllers for miniaturization. The clock output signal enables two or more SC2441As to be daisy chained with programmable phase shift. Tying the FB2 pin to VIN makes the second step-down channel a slave of the first. Operating in this mode, the SC2441A regulates a single output with shared current in each channel. Each step-down controller has its own softstart and overload shutdown timer for hiccup overload protection. In the single-output mode, the channel 1 timer controls the soft-start and overload hiccup of both controllers.
SC2441A
Features
2-Phase Synchronous Step-down Controllers u 2-Phase Synchronous Continuous Conduction Mode u Out of Phase Operation for Low Input Current Ripple u Operates up to 1MHz Per Channel u Excellent Current Sharing Between Phases u Duty Cycle Up to 90% u 0.5V Feedback voltages for Low-Voltage Outputs u Starts into Pre-biased Outputs u Adaptive Shoot-through Protection u Lossless Inductor DCR Current Sensing u 23mV Current-limit Threshold u Individual...