Refine
Document Type
Language
- English (2) (remove)
Has full text
- yes (2)
Is part of the Bibliography
- yes (2)
Institute
- Technik (2)
Publisher
- Hochschule Ulm (2) (remove)
A millimeter-wave power amplifier concept in an advanced silicon germanium (SiGe) BiCMOS technology is presented. The goal of the concept is to investigate the impact of physical limitations of the used heterojunction bipolar transistors (HBT) on the performance of a 77 GHz power amplifier. High current behavior, collectorbase breakdown and transistor saturation can be forced with the presented design. The power amplifier is manufactured in an advanced SiGe BiCMOS technology at Infineon Technologies AG with a maximum transit frequency fT of around 250 GHz for npn HBT’s [1]. The simulation results of the power amplifier show a saturated output power of 16 dBm at a power added efficiency of 13%. The test chip is designed for a supply voltage of 3.3 V and requires a chip size of 1.448 x 0.930 mm².
A fast transient current-mode buckboost DC-DC converter for portable devices is presented. Running at 1 MHz the converter provides stable 3 V from a 2.7 V to 4.2 V Li-Ion battery. A small voltage under-/overshoot is achieved by fast transient techniques: (1) adaptive pulse skipping (APS) and (2) adaptive compensation capacitance (ACC). The proposed converter was implemented in a 0.25 μm CMOS technology. Load transient simulations confirm the effectiveness of APS and ACC. The improvement in voltage undershoot and response time at light-to-heavy load step (100 mA to 500 mA), are 17 % and 59 %, respectively, in boost mode and 40 % and 49 %, respectively, in buck mode. Similar results are achieved at heavy-to-light load step for overshoot and response time.