A spurious-free switching buck converter using a delta-sigma modulation controller with a scalable sampling frequency

This switching DC-DC buck converter uses a ΔΣ-modulator controller with a scalable sampling frequency, in order to eliminate the spurs and minimize the noise floor at its output without sacrificing the power efficiency. Fabricated in 0.13-μm digital CMOS, it achieves a spurious-free output with voltage ripples below 70mV over its full loading range (2mA to 800mA). Furthermore, its power efficiency is higher than 72% over this range, with 96% peak efficiency.