This article presents a study on the short-circuit (SC) instability of p-doped gate gallium nitride (p-GaN) high-electron-mobility transistors (HEMTs). Under SC condition, self-sustained oscillation occurs when a package stray inductance is introduced in a common source. The SC oscillation features some unique characteristics. With higher dc-bus voltage, the SC oscillation tends to be more unstable. The SC oscillation of p-GaN HEMTs is, thereby, a real threat to the converter operation. When the common-source inductance is eliminated or a larger gate resistor is utilized, the SC oscillation can be dampened. Due to the SPICE simulation, the self-sustained SC oscillation is reproduced. The analyses on the simulated waveforms reveal a positive feedback mechanism that excites the SC oscillation. An analytical model is, thereby, derived to analyze the instability of the positive feedback system. The analyses reveal that the SC oscillation becomes more unstable when the power loop or gate loop has smaller stray inductances, which makes some conventional oscillation suppression methods invalid. To avoid SC oscillation, some effective guidelines are proposed at the end of the article.

中文翻译：

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p-GaN HEMT 短路振荡的综合研究

本文介绍了对 p 掺杂栅极氮化镓 (p-GaN) 高电子迁移率晶体管 (HEMT) 的短路 (SC) 不稳定性的研究。在 SC 条件下，当在公共源中引入封装杂散电感时，会发生自持振荡。SC 振荡具有一些独特的特性。直流母线电压越高，SC 振荡越不稳定。因此，p-GaN HEMT 的 SC 振荡是对转换器操作的真正威胁。当消除共源电感或使用更大的栅极电阻时，可以抑制 SC 振荡。由于 SPICE 模拟，可重现自持 SC 振荡。对模拟波形的分析揭示了激发 SC 振荡的正反馈机制。因此，一个分析模型是 推导分析正反馈系统的不稳定性。分析表明，当功率回路或门回路具有较小的杂散电感时，SC振荡变得更加不稳定，这使得一些传统的振荡抑制方法无效。为避免SC振荡，文章最后提出了一些有效的指导方针。