Description

This document summarizes some tips for designing peripheral circuits that should be noted when you use the VCE(sat) detection function of a smart gate driver coupler such as TLP5214A/TLP5214/TLP5212/TLP5222. The VCE(sat) detection (DESAT detection) circuit which detects the rise of the collector or drain voltage (VCE) when an over-current flows into the power semiconductor switch device (hereinafter referred to ‘power device’) driven by the gate driver by causes, such as a short circuit of load, makes the power device turn off, and protects it. However, the VCE may rise unusually and largely due to the inductances of the loads when the power device switches, and if it enters the DESAT terminal, an erroneous detection of the DESAT detection circuit may occur. In three-phase inverters and other inverters, noise generated during switching of other phases may cause an erroneous detection of the DESAT detection circuit due to noise circulating through power supply lines and GND lines or electromagnetic induction between wires. This document provides tips to reduce the likelihood of DESAT false detections.