This paper deals with the design techniques of power efficient switching regulators intended for linear power amplifiers employing envelope tracking techniques in wideband wireless standards. The bottlenecks involve a tradeoff between ripple voltage, slew rate and bandwidth. The slew rate limitation is identified as the main challenge, then a ‘bang-bang’ slew enhancement technique is proposed. This approach enables the use of efficient supply modulators in wideband power amplifiers. The proposed scheme does not significantly degrade PA efficiency and preserves the stability of the switching regulator. The prototype has been implemented using the TSMC 0.18 µm technology; schematic simulation results in Cadence® are presented to prove the concept.
CitacióMartinez, H.; Turkson, R.; Silva-Martínez, J. ‘Bang-Bang’ technique in supply modulation for linear wideband RF power amplifiers. A: Conference on Design of Circuits and Integrated Systems. "Proceedings of the XVIII Conference on the Design of Circuits and Integrated Systems (DCIS 2013)". San Sebastián - Donostia: Universidad de Navarra, 2013, p. 16-19.