STMicroelectronics introduces isolated gate drivers

     STGAP2SiCS is the latest in ST's STGAP family of isolated gate drivers that securely control silicon carbide (SiC) MOSFETs with operating power supply voltages up to 1200V. STGAP2SiCS generates a gate drive voltage of up to 26V and increases the under-voltage lock (UVLO) threshold to 15.5V, meeting the normal on-going requirements of SiC MOSFET switches. If the drive voltage is too low due to low power supply, the UVLO protection mechanism will ensure that the MOSFET is turned off so as not to generate too much dissipated power. The driver has two input pins that allow designers to define the polarity of the gate drive signal.

     STGAP2SiCS designs a 6kV electrical isolation between the input part and the gate drive output, which helps ensure the safety of electricity consumption in consumer electronics and industrial equipment. 4A current absorption/pull current drive capability makes it suitable for high power converters, power supplies and inverters for high-end household appliances, industrial drives, fans, induction cookers, welders, UPS uninterruptible power supplies and other equipment.

     The new product comes in two different output configurations. The first configuration provides individual output pins that can be independently optimized for on-off times using dedicated gate resistors. The second configuration is suitable for high frequency hard switches with only one output pin and an active Miller clamp circuit, which is used to limit the gate-source voltage swing of the SiC MOSFET, prevent unnecessary switching, and enhance the reliability of the switch. The input circuit is compatible with a minimum 3.3V CMOS/TTL logic level signal and can be easily connected to various controller chips.

     STGAP2SiCS has a standby mode that helps reduce system power consumption and has internal protection features, including hardware interlocking and thermal shutdowns that prevent cross-conduction of low-voltage parts and high-voltage drive channels. The propagation delay between low and high voltage circuits is precisely matched to prevent cycle distortion and minimize power loss. The total propagation delay is less than 75ns, and precise pulse width modulation (PWM) control supports high switching frequencies.