Torex Semiconductor’s XCL223 and XCL224 series of step-down converters pack an inductor and control IC in a single 2.25×1.5×0.75-mm package, simplifying board layout. Despite their miniaturization and reduced height, the synchronous converters deliver an output current of 400 mA or 700 mA. by Susan Nordyk @ edn.com:
An operating voltage range of 2.5V to 5.5V accommodates applications that require an internally fixed output voltage of 0.8 V to 3.6 V. Output voltage is selectable in 0.05 V steps, accurate to within ±2.0%. Both the XCL223 and XCL224 series use synchronous rectification at an operating frequency of 3.0 MHz. The XCL223 converters offer PWM control, while the XCL224 converters provide PWM/PFM auto-switching control.
Mini DC/DC converters integrate coil – [Link]