Design Techniques of Sub-ns Level Shifters With Ultrahigh dV/dt Immunity for Various Wide-Bandgap Applications

In high-frequency gate drivers, especially for wide-bandgap applications, hundreds of voltages per nanosecond noise would be generated. Therefore, the sub-ns delay level shifter with high dV/dt immunity is necessary for signal conversion among different voltage domain areas. This article presents design techniques for the sub-ns delay level shifter with ultrahigh dV/dt immunity. The propagation delay of the proposed floating level shifter is dramatically reduced by utilizing the edge detection technique. In order to further improve the performance, auxiliary pull-up circuit, promoting delay matching, and self-calibration techniques are adopted, which make the proposed level shifters more suitable for high-frequency wide-bandgap applications. The level shifter is fabricated in a 0.5 μm bipolar CMOS DMOS (BCD) process, whose results demonstrate the final level shifter achieves zero static power consumption, a 0.024 mm
²
active area, and dV/dt immunity up to 250 V/ns. The measurement results show that the sub-ns delay level shifter can be realized, and the minimum delay is only 664 ps at VSSH 25 V. Its figure of merit is just 0.044 ns/(μm × V), which is optimal among previous level shifters. The level shifters are also simulated at the 0.18 μm BCD process, and the propagation delay can be decreased by more than 60%.