IGBT device with integrated voltage sampling function

Abstract

The invention provides an IGBT device with an integrated voltage sampling function, and belongs to the technical field of power semiconductor devices. A channel in which a JFET structure is introducedin a body region is in a normally-closed state, the device is in a forward turning-on state, and carriers are stored in the body region, so that an electric conductance modulating action is strengthened, and the saturated turning-on voltage drop of the device is reduced; in a turning-off state of the device, the body region plays a floating field limiting ring role, so that an electric field aggregation phenomena at the bottom of a groove gate is weakened, and the voltage withstand reliability of the device is improved; the grid electrode and the source electrode of the introduced JFET structure are connected with a peripheral control circuit and a sampling port respectively, a voltage sampling function can be realized by using a mapping reaction between the voltage change of the source electrode of the JFET structure and withstanding voltage of an IGBT, and the forward blocking characteristic of the device cannot be damaged while an electric isolation effect is reached; and the adjustment for voltage sampling rate is realized by changing the grid electrode bias voltage of the JFET structure, so that the requirement of different application conditions on voltage sampling is met. The IGBT device is simple in sampling structure, and is compatible with an existing technology.

Description

Technical field [0001] The invention belongs to the technical field of power semiconductor devices, and specifically relates to an IGBT device with an integrated voltage sampling function. Background technique [0002] With the rapid development of high-speed railways, new energy vehicles and other transportation tools, insulated gate bipolar transistors (IGBTs) have become the most popular in power electronics applications due to their simple gate control, high current density, and reduced conduction voltage. One of the mainstream power switching devices. In order to meet the high-power or ultra-high-power requirements in practical applications, IGBT devices are usually packaged in modules. In practical applications, overvoltages usually occur at both ends of the chip, so that the blocking capability of the device is limited by avalanche breakdown, and the avalanche tolerance parameter of the IGBT directly characterizes the avalanche resistance of the device. When an overvolta...

AI Technical Summary

Problems solved by technology

figure 1 It is a schematic diagram of the voltage sampling structure of a traditional IGBT device. This kind of voltage sampling structure needs to be isolated from the IGBT cell structure by "Gate Runner", which has no effect on the IGBT current conduction and requires additional chip area; at the same time As the sampling voltage level increases, the voltage value collected by the voltage sampling port will rise rapidly, the electrical isolation of the voltage sampling structure will be weakened accordingly, and the mapping relationship between the sampling voltage and the IGBT terminal voltage will also be weakened, resulting in a significant increase in sampling accuracy. decline

In addition, the traditional voltage sampling structure cannot realize the adjustment of the voltage sampling ratio when the device size is fixed, which is limited by the voltage level of the high-voltage application circuit

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