Gate drivers simplify the switching of MOSFETs and IGBTs

18th May 2017

Alice Matthews

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A range of gate drivers that feature a floating high-side driver has been introduced by Diodes. The DGD2103M, DGD2104M and DGD2304 simplify the switching of two N-channel MOSFETs or two IGBTs in a half-bridge configuration. These drivers suit a wide range of motor control and power supply applications in industrial automation and white goods, that require AC and DC motor control boards rated above 100W, and LLC resonant converter power supply topologies.

The half-bridge configuration of the DGD2103M, DGD2104M and DGD2304 devices includes high-side (HS) and low-side (LS) drivers with high pulse-current outputs to provide effective switching of low RDS(on) MOSFETs or IGBTs, and increase overall system efficiencies. Shoot-through prevention logic includes closely matched delay times and a fixed internal deadtime to protect the HS and LS power switches by ensuring they are not on simultaneously. The floating high-side driver provides high-voltage isolation allowing operation on power rails up to 600V.

Compatible with logic-level inputs from 2.5V, these gate drivers further simplify the driving of power switches by enabling direct PWM control from 3.3V MCUs, while the gate drive output operates up to the VCC supply (10-20V) to minimise conduction losses in the switch. The DGD2103M and DGD2104M have optimised Schmitt trigger inputs to avoid false triggering in noisy motor applications; while the DGD2304 provides a shorter internal deadtime, typically 100ns, making it a better choice for high-frequency applications. Additional self-protection features include a gate drive that is tolerant to negative transients arising from high dV/dt switching, and undervoltage lockout (UVLO) to avoid malfunction under low supply voltage conditions.