Gate driver

About: Gate driver is a research topic. Over the lifetime, 7532 publications have been published within this topic receiving 75854 citations.

An analytical model of IGBTs with low emitter efficiency

Abstract: An IGBT (insulated-gate bipolar transistor) model has been developed which describes the static and dynamic characteristics of IGBTs with low emitter efficiency and high charge carrier lifetime. Simple equations for the IGBT current and stored charge are obtained from calculations that take into account the dynamic behavior of the charge carriers which are injected into the base layer. The model has been implemented in the circuit simulator SABER. Simulation results show that measured IGBT characteristics like on-state voltage, storage time and tail current are well reproduced. The model can be enhanced to include the other types of IGBTs if the recombination term p/ tau is not neglected. >

A fully integrated three-level 11.6nC gate driver supporting GaN gate injection transistors

Abstract: Due to their superior fast-switching performance, GaN transistors show enormous potential to enable compact power electronics in applications like renewable energy, electrical cars and home appliances by shrinking down the size of passives. However, fast switching poses challenges for the gate driver. Since GaN transistors have a low threshold voltage V t of ∼1V, an unintended driver turn-on can occur in case of a unipolar gate control as shown for a typical half-bridge in Fig. 24.2.1 (top left). This is due to coupling via the gate-drain capacitance (Miller coupling), when the low-side driver turns on, causing a peak current into the gate. This is usually tackled by applying a negative gate voltage to enhance the safety margin towards Vt, resulting in a bipolar gate-driving scheme. In many power-electronics applications GaN transistors operate in reverse conduction, carrying the inductor current during the dead time t, when the high-side and low-side switch are off (as illustrated at a high-side switch in Fig. 24.2.1, bottom left). As there is no real body diode as in silicon devices, the GaN transistor turns on in reverse operation with a voltage drop V F across the drain-source terminals (quasi-body diode behavior). As a negative gate voltage adds to V F , 63% higher reverse-conduction losses were measured for a typical GaN switch in bipolar gate-drive operation. This drawback is addressed by a three-level gate voltage (positive, 0V, negative), which at the same time provides robustness against unintended turn-on similar to the bipolar gate driver, proven in [1] for a discrete driver.

A 4H Silicon Carbide Gate Buffer for Integrated Power Systems

Abstract: A gate buffer fabricated in a 2-μm 4H silicon carbide (SiC) process is presented. The circuit is composed of an input buffer stage with a push-pull output stage, and is fabricated using enhancement mode N-channel FETs in a process optimized for SiC power switching devices. Simulation and measurement results of the fabricated gate buffer are presented and compared for operation at various voltage supply levels, with a capacitive load of 2 nF. Details of the design including layout specifics, simulation results, and directions for future improvement of this buffer are presented. In addition, plans for its incorporation into an isolated high-side/low-side gate-driver architecture, fully integrated with power switching devices in a SiC process, are briefly discussed. This letter represents the first reported MOSFET-based gate buffer fabricated in 4H SiC.

Systems and methods for load compensation with primary-side sensing and regulation for flyback power converters

Abstract: System and method for regulating an output voltage of a power conversion system. The system includes a sampling component located on a chip configured to receive an input voltage through a terminal. The sampling component is configured to sample the input voltage and generate a sampled voltage. Additionally, the system includes an error amplifier configured to process information associated with the sampled voltage and a threshold voltage and generate a first output signal, and a first signal generator configured to generate a second output signal and one or more third output signals. Moreover, the system includes a comparator configured to receive the first output signal and the second output signal and generate a comparison signal, and a gate driver directly or indirectly coupled to the comparator and configured to generate a drive signal based on at least information associated with the comparison signal.

Power supply apparatus, method for driving power supply apparatus, light source apparatus equipped with power supply apparatus, and electronic apparatus

Abstract: A power supply apparatus includes an AC/DC circuit, a DC/DC converter, a detection circuit, a digital IC, and a gate driver, and the like. A control formula used for phase compensation for each of a plurality of drive frequencies is stored in a memory of the digital IC. The power supply apparatus makes it possible to obtain a target voltage quickly by performing driving operation with a driving signal having a higher drive frequency at the time of activation. In addition, the power supply apparatus makes it possible to increase circuit efficiency by switching over from the driving signal having the higher drive frequency to a driving signal having a lower drive frequency upon reaching the target voltage.