SI9978DW-T1-E3

SI9978DW-T1-E3 are Gate Drivers integrated circuits (IC) designed to provide high-current drive capability at an appropriate voltage level for powering an electronic switch, such as an N-channel or P-channel MOSFET or insulated gate bipolar transistor (IGBT). They are classified as PMIC - Gate Drivers and belong to Monolithic Power System’s (MPS) Power Management Integrated Circuit (PMIC) family of products.

SI9978DW-T1-E3 provide adjustable switching characteristics, such as Rise-Time control and fall-time control, adjustable gate drive current, adjustable soft-start, adjustable dead-time control as well as other features such as under-voltage lockout and shutdown control. This IC supports up to 20V voltage levels and provides a maximum current of up to 4A. All these features make SI9978DW-T1-E3 suitable for many switch-mode applications, such as computer server, GPU, LCD monitor, charger and so on.

SI9978DW-T1-E3 Application Field

Gate Drivers are used to control the turn-on/turn-off timing of the switches such as MOSFET or IGBT in the switch-mode power supplies (SMPS). Benefits of using Gate Drivers are reduced switching losses, improved surge current handling ability, improved noise immunity, improved EMC performance and so on. SI9978DW-T1-E3 is a highly integrated Gate Driver device specially designed for the switch mode power supplies. It is suitable for synchronous buck, boost and buck-boost topologies, especially in the voltage range from 3.3V to 20V.

The SI9978DW-T1-E3 is also suitable for other applications, such as partial or full-bridge topologies for hard disk and motor control in the automotive, telecom, telecom/network/storage (TNS) and high-temperature applications due to its robust feature set and wide operating temperature range of -40°C to 130°C. It also comes in an industry-standard 4mm x 4mm QFN package, making it suitable for high-density applications.

SI9978DW-T1-E3 Working Principle

SI9978DW-T1-E3 consists of a high-side and low-side gate driver that can drive, control and synchronize two power switches. A typical application of SI9978DW-T1-E3 would be to drive pairs of N-channel (NMOS) and/or P-channel (PMOS) MOSFETs. The high-side MOSFETs are connected to the VCC and their gates to the high-side gate driver. And the low-side MOSFETs are connected to the ground and their gates to the low-side gate driver. These two Gate Drivers are then controlled by a signal. This signal is generated by the internal control and monitoring circuitry present in the SI9978DW-T1-E3.

SI9978DW-T1-E3 also has an internal linear regulator (LINREG) that provides a regulated output voltage. The LINREG rail provides the gate driver supply voltage, hence the gate voltage is always within the regulated voltage range and the gate drivers generate the appropriate voltage for the switches.

SI9978DW-T1-E3 also has an adjustable current limiter that allows for the prevention of current overload conditions. It also provides adjustable dead-time control to allow for the reduction of shoot-through current and adjustable soft-start to reduce voltage overshoots. Lastly, it features under-voltage protection, over- temperature protection and shutdown control.

Conclusion

Gate Drivers are essential and crucial components in switch-mode power supplies. SI9978DW-T1-E3 is a high-performance, high-efficiency Gate Driver device specially designed for SMPS applications. It comes with adjustable control and monitoring circuitry, adjustable current limiting, adjustable dead-time control and adjustable soft-start and shutdown control. These features make SI9978DW-T1-E3 suitable for a large number of switch-mode applications - computer server, GPU, LCD monitor, charger, automotive, TNS, and high-temperature applications.