STMicroelectronics’ New Isolated Gate Driver is Aimed At SiC MOSFETS
The new driver delivers gate-driving voltages of up to 26 volts and operates from a high-voltage rail up to 1200V
The STGAP2SICS from STMicroelectronics (ST) is a single gate, 4 amp SiC MOSFET driver that features a full 6kV of galvanic isolation, separating the low voltage control and interface section from the powerful gate driving channel.
The STGAP2SiC. Image courtesy of ST
Driving and Controlling SiC MOSFETS
The STGAP2SiCS can provide up to 26 volts, but if output goes below 15.5 volts, the unit’s under-voltage lockout (UVLO) will cause the MOSFET to shut down. Whether or not the low driving voltage is caused by a low power supply voltage, this valuable feature will prevent excessive dissipation.
The unit’s input is compatible with CMOS/TTL logic levels as low as 3.3 volts. This serves to allow easy interfacing with industry standard control ICs.
Two Distinct Output Configurations
The first configuration, available as model number STGAP2SICSCTR, is suited to high-frequency hard switching. It features a single output pin and an active Miller clamp. This limits the oscillation of the SiC MOSFET gate-source voltage, preventing unwanted turn-on and serving to enhance reliability.
The STGAP2SiCS gate driving channel in its single output with Miller clamp mode. Image courtesy of ST’s datasheet
The second configuration, available as model STGAP2SICSTR, features separate output pins allowing for independent optimization of turn-on and turn-off times through the employment of dedicated gate resistors.
The STGAP2SiCS’s gate driving channel in separate output mode. Image courtesy of datasheet
Here, GON and GOFF are source and sink outputs, respectively.
Features and Specifications of the STGAP2SiCS
On the input side, dual input pins allow designers to determine the gate-drive signal polarity. A standby mode is available to reduce power consumption when the driver is idle.
The maximum voltage supplying the control and interface section is 6.5 volts
The maximum voltage that the inputs to the control and interface section can tolerate is also 6.5 volts
- The maximum powers supply voltage for the gate driving section is 28 volts
Recommended Operating Voltages
For the control and interface section, ST recommends 5.5 volts for both power supply and data inputs
For the gate driving section, 26 volts is recommended
- Maximums switching speed is 1 MHz
- Output pulse width: 100 nanoseconds
Thermal resistance, junction to ambient (RTH(JA)): 118 °C/W
- Standby Time: 200 μs (typ)
- Wake-up time: 20 μs (typ)
- Wake-up delay:140 μs (typ)
- Standby filter: 280 μs (typ)
The STGAP2SiCS’ 4A output-sink/source capability suits it for use in:
- Power convertors
- Power supplies
- Industrial drives
- Induction heaters
- Home appliances
- The driver is available in an SO-8W package, maximum dimensions of 6.05 by 10.52 mm (including gull wings)
- Operation is over a -40 to +150℃ temperature range
Regulatory and Safety Features
- Electrostatic discharge (ESD) protection, human body model (HBM), is 2 kilovolts
- The device features 8 mm of creepage, measured from input to output terminals