Resonant gate drivers were originally developed to recover part of MOSFET gatedrive loss when operating at high switching frequency. Most of investigations are generally emphasizing gate energy savings by the resonant driver and concentrating on the drive topologies, but ignore the potential switching loss savings that are much more dominant in MHz switching power converter. The idea of the CSDs is to build strong gate-drive current during the switching transition to realize quick turn-on and turn-off transition and reduce high-frequency switching loss and gate-drive loss in power MOSFETs. The switching loss characteristics and behavior in a high-frequency synchronous buck VR is investigated and the parasitic inductances act as a current snubber at turn on to reduce turn-on loss, but prolong the turn-off time and increase turn-off loss.

Chapter Contents:

• 2.1 Resonant gate drivers
• 2.2 Concept of current source driver
• 2.3 A practical and accurate switching loss model
• 2.3.1 Introduction
• 2.3.2 Impact of parasitic inductance and load current
• 2.3.3 Proposed switching loss model
• 2.3.4 Turn-on switching loss model
• 2.3.4.1 Rise time interval T1r: charging HS MOSFET Cgs1 and Cgd1 gate capacitances
• 2.3.4.2 Rise time interval T2r: charging the HS MOSFET Cgd1 gate capacitance
• 2.3.5 Turn-off switching loss model
• 2.3.5.1 Fall time interval T1f: discharging the HS MOSFET Cgd1 gate capacitance
• 2.3.5.2 Fall time interval T2f: current falling and discharging the HS MOSFET Cgs1 and Cgd1 gate capacitances
• 2.3.6 Voltage source drive model verification
• 2.3.7 Experimental validation of the voltage source drive model
• 2.4 Summary
• References

Inspec keywords: power MOSFET; driver circuits; switching convertors; voltage regulators; snubbers

Other keywords: drive topologies; switching loss characteristics; turn-off loss; CSDs; current snubber; high-frequency synchronous buck VR; turn-on loss; power MOSFETs; gate energy savings; high switching frequency; current source driver; parasitic inductances; gate-drive current; MOSFET gate-drive loss; MHz switching power converter; resonant gate drivers; high-frequency switching loss; turn-off time; potential switching loss savings; turn-on transition; turn-off transition; switching transition

Subjects: Power semiconductor devices; Power electronics, supply and supervisory circuits; Insulated gate field effect transistors