ESD protection design for broadband RF circuits with decreasing-size distributed protection scheme

The resulting capacitive load, from a large electrostatic discharge (ESD) protection device for high ESD robustness, has an adverse effect on the performance of broadband RF circuits due to the impedance mismatch and bandwidth degradation. The conventional distributed ESD protection scheme, using equal four-stage ESD protection can achieve a better impedance match, but degrades the ESD performance. A new distributed ESD protection structure is proposed in this work, to achieve both good ESD robustness and RF performance. The proposed ESD protection circuit is constructed by arranging ESD protection stages with decreasing device size, named decreasing-size distributed ESD (DS-DESD) protection scheme, which is beneficial to the ESD level. The experimental results have shown a human-body-model (HBM) ESD robustness of up to 8 kV.