A gate driver IC is used to produce a high current to drive the gate terminal of a power transistor such as a MOSFET, IGBT, GaN transistor, etc. A typical controller circuit does not produce enough current to drive the gate terminal of these power transistors. Hence, the gate driver IC acts as an interface between the controller circuitry and power transistors. Gate driver ICs are also called level shifter ICs as they are used to shift the low voltage signal (which cannot directly drive the gate of the power transistor) into a suitable high-voltage level to drive the gate terminal of a power transistor.

Key Features of Gate Driver ICs:

• Low Undervoltage lockout (UVLO) – It is a type of electronic circuit that is used to turn off the power of a gate driver IC in the event of the voltage dropping below the operational value.
• Fast propagation delay - The propagation delay is the time taken for an input edge to reach the output. It depends on the driver’s output current and the output load.
• Integrated bootstrap diode.
• High driving current.
• Over-current protection.

Gate driver ICs are ideal for applications such as motor drives, switch-mode power supplies, pulse transformer drives, line drivers, level translator, motor & solenoid drives, PFC, battery-powered equipment, computing, lighting, and solar micro-inverter.

Configuration of Gate Driver IC:

Isolated gate driver IC: The isolated gate driver IC utilizes optocouplers or on-chip micro transformers to provide electrical isolation for the safety of the driver circuit. This IC isolates the grounds and noise coupling between the controller IC and the power transistor (MOSFET, IGBT, GaN transistor, etc.)

Non-isolated gate driver IC: In this configuration, the controller IC and the power transistor share a common ground. This type of configuration does not provide any isolation between the controller IC and the power transistor (MOSFET, IGBT, GaN transistor, etc.).

Specifications of Gate Driver ICs:

Types of gate driver: The gate driver ICs are available both in single-channel (one gate drive output) and dual-channel (two gate drive outputs) options.

Configuration: The gate driver ICs are available in different configurations, such as isolated and non-isolated gate driver ICs.

Number of drivers: It represents the number of gate drivers available in an IC package. The gate driver IC package is available with single and dual gate drivers’ choices.

Number of outputs: It represents the number of gate driver outputs. This usually equals the number of drivers.

Input voltage: It represents the input voltage of the gate driver IC and is expressed in volts (V). The input voltage is the voltage output of a controller IC, which will be converted into a suitable high voltage to drive the gate of the power transistor by the gate driver IC.

Output voltage: It represents the output voltage that is provided by the driver IC and is expressed in volts (V).

Isolation voltage: It represents the highest voltage that can be applied across a gate driver IC for one second without compromising the isolation in the device. It is expressed in volts (V).

Output current: It represents the maximum output current that can be provided by a gate driver IC to drive the gate. It is expressed in Ampere (A).

Rise time: It represents the time required for the output of the gate driver IC from 10% to reach 90% of its final value.

Fall time: It represents the time required for the output of the gate driver IC from 90% to reach 10% of its final value.

Propagation delay:  The propagation delay is the time taken for an input edge to reach the output. It depends on the driver’s output current and the output load.

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