SC1404 Datasheet | SEMTECH

Description The SC1404 is a multiple-output power supply controller designed to power battery operated systems. The SC1404 provides synchronous rectified buck converter control for two power supplies. An efficiency of 95% can be achieved. The SC1404 uses Semtech’s proprietary Virtual Current Sense TM technology along with external error amplifier pensation to achieve enhanced stability and DC accuracy over a wide range of output filter ponents while maintaining fixed frequency operation. The SC1404 also provides two linear regulators for system housekeeping. The 5V linear regulator takes its input from the battery; for efficiency, the output is switched to the 5V output when available. The 12V linear regulator output is generated from a coupled inductor off the 5V switching regulator. Control functions include: power up sequencing, soft start, powergood signaling, and frequency synchronization. Line and load regulation is to +/-1% of the output voltage. The internal oscillator can be adjusted to 200 k Hz or 300 k Hz or synchronized to an external clock. The MOSFET drivers provide >1A peak drive current for fast MOSFET switching. The SC1404 includes a PSAVE# input to select pulse skipping mode for high efficiency at light load, or fixed frequency mode for low noise operation. Features 6 to 30V input range (operation possible below 6V) 3.3V and 5V dual synchronous outputs Fixed-frequency or PSAVE for maximum efficiency over wide load current range 5V/50m A linear regulator 12V/200m A linear regulator TM Virtual Current Sense for enhanced stability Accurate low-loss current limiting Out-of-phase switching reduces input capacitance External pensation supports wide range of output filter ponents for reduced cost Programmable power-up sequence Power Good output Output overvoltage & overcurrent protection with output undervoltage shutdown 4µA typical shutdown current 6m W typical quiescent power Applications Notebook and Subnotebook puters Automotive Electronics...