Single-chip GaN gate driver accelerates automation, says STMicroelectronics
STMicroelectronics’ STDRIVEG600 half-bridge gate driver has high current output and 45ns propagation delay, closely matched between high-side and low-side outputs, in order to handle high frequency switching of GaN enhancement-mode FETs.
The driver can also be used for driving N-channel silicon MOSFETs at up to 20V, and allows up to 6V gate source voltage (VGS) to be applied on GaN devices to ensure low Rds(on). The driver also has an integrated bootstrap circuit that helps minimise the bill of materials (BoM) and to simplify board layout, claims STMicro. The bootstrap circuit uses a synchronous MOSFET that lets the bootstrap voltage reach the logic supply voltage, VCC, allowing the driver to operate from a single supply without a low dropout regulator (LDO).
The STDRIVEG600 has dV/dt immunity of ±200V/ns for dependable gate control in challenging electrical environments. The logic inputs are CMOS / TTL -compatible down to 3.3V for easy interfacing with a host microcontroller or DSP. The high side section withstands up to 600V, allowing use in applications with a high voltage bus up to 500V.
In addition, the outputs have 5.5 / 6.0A sink / source capability and provide separated turn-on and turn-off pins. As a result, designers can choose the optimum way to control the gate. Both the high side and low side circuits support Kelvin connection to the power switch source for enhanced control. Dedicated ground and supply voltage connections for the low side driver ensure stable switching with the Kelvin connection and allow a shunt resistor to be used for current sensing without additional isolation or input filtering.
Built-in safety functions include under-voltage lockout (UVLO) on both the lower and upper driving sections to prevent the power switches from operating in low efficiency or dangerous conditions. There is also interlocking to avoid cross-conduction, as well as over-temperature protection. A dedicated pin for shutdown functionality is also available.
The STDRIVEG600 can be used in applications such as high voltage PFC, DC/DC, and DC/AC converters, switched mode power supplies, UPS systems, solar generators, and motor drivers for home appliances, factory automation and industrial drives.
The STDRIVEG600 is in full production and available as a 16-pin SO16 device.
Two development boards are available. The first is the EVSTDRIVEG600DG which contains a 150mOhm 650V GaN HEMT in 5.0 x 6.0mm PowerFLAT package with Kelvin source. The second is the EVSTDRIVEG600DM which comes with a STL33N60DM2 MDmesh 115mOhm 600V silicon power MOSFET with fast recovery diode in 8.0 x 8.0mm PowerFLAT with Kelvin source or alternative DPAK package.
