Monolithic 1Amp DC:DC Step-down Regulator

The EL7551 is an integrated, synchronous step-down regulator with output voltage adjustable from 1.0V to 3.8V. It is capable of delivering 1A continuous current at up to 95 efficiency. The EL7551 operates at a constant frequency pulse width modulation (PWM) mode, making external synchronization possible. Patented on-chip resistorless current sensing enables current mode control, which provides cycle-by-cycle current limiting, over-current protection, and excellent step load response. The EL7551 is available in a fused-lead 16-pin QSOP package. With proper external components, the whole converter fits into a less than 0.4 in2 area. The minimal external components and small size make this EL7551 ideal for desktop and portable applications.

Features

• Integrated synchronous MOSFETs and current mode controller

• 1A continuous output current

• Up to 95 efficiency

• 4.5V to 5.5V input voltage

• Adjustable output from 1V to 3.8V

• Cycle-by-cycle current limit

• Precision reference

• ±0.5 load and line regulation

• Adjustable switching frequency to 1.2MHz

• Oscillator synchronization possible

• Internal soft start

• Over temperature protection

• Under voltage lockout

• 16-pin QSOP package

• Pb-free plus anneal available (RoHS compliant)

Applications

• DSP, CPU Core and IO Supplies

• Logic/Bus Supplies

• Portable Equipment

• DC:DC Converter Modules

• GTL + Bus Power Supply