Gate drivers are electronic circuits that apply correct power levels to metal-oxide field-effect transistors (MOSFETs) and insulated gate bipolar transistors (IGBTs). With power-MOSFETs, gate drivers can be implemented as transformers, discrete transistors, or dedicated integrated circuits (IC).

They can also be integrated within controller ICs. Partitioning the gate-drive function of controllers that use pulse width modulation (PWM) improves controller stability by eliminating the high peak currents and heat dissipation needed to drive power-MOSFETs at very high frequencies.

With IGBTs, gate drivers serve as isolation amplifiers and often provide short-circuit protection. Because of their insulated gates, IGBTs require a continuous gate circuit in order to sustain gate current.

Types of Drivers

There are four basic types of gate drivers. High-side gate drivers are used to drive power-MOSFETs or IGBTs that are connected to a positive supply and not ground referenced (floating). Conversely, low-side gate drivers are used to drive power-MOSFETs and IGBTs that are connected to a negative supply.

Dual gate or half-bridge gate drivers have both low-side and high-side gates. Three-phase drivers derive their name from the fact that they are used in three-phase applications. These drivers have three independent low-side and high-side referenced output channels. Typically, gate drivers have 1, 2, or 4 output channels. Their output voltage can be either inverted or non-inverted.  

Performance Specifications

• Output voltage
• Peak output current
• Supply voltage
• Rise time
• Fall time
• Propagation delay
• Power dissipation
• Switching frequency
• Operating temperature

Rise time is the time needed for the output voltage to increase from 10% to 90% of maximum. Conversely, fall time is the time needed for the output voltage to decrease from 90% to 10% of the maximum.

Features

• Input threshold
• Integrated protection
• Dead time control
• Internal regulation

Input thresholds consist of transistor-transistor logic (TTL), complementary metal-oxide semiconductor (CMOS), pulse width modulation, and combinations such as TTL/CMOS and TTL/PWM. Integrated protection types include over-voltage protection (OVP), over-voltage protection current (OVPC), undervoltage lockout (UVLO), thermal shutdown (TSD), and over-current protection (OCP). Dead time control eliminates shoot-through currents. Internal regulation controls the level of the output voltage. 

Packaging Options

• Ball-grid array (BGA)
• Chip scale package (CSP)
• Quad flat package (QFP)
• Small outline package (SOP)
• Single in-line package (SIP)
• Dual in-line package (DIP).

Fine-pitch land grid array (FLGA) and SC-70, one of the smallest IC packages, are also available. Packing methods for gate drivers include tape reels, tubes, bulk packs, and trays or rails. Screening levels such as commercial, industrial, and military indicate the supported temperature range as well as mechanical and electrical specifications. Some listed gate drivers are still in development. Others are in full production. Devices that are discontinued are no longer available from the manufacturer, but may still be found in the supply chain.

Related Standards

SMD 5962-99511 - Microcircuit, digital-linear, radiation hardened dual inverting mosfet driver, monolithic silicon.

SMD 5962-01521 - Microcircuit, digital-linear, radiation hardened, 9 amp non-inverting mosfet driver, monolithic silicon.

MIL-PRF-28776/7 - Relays, hybrid, established reliability, dpdt, low level to 1.0 ampere (sensitive coil operate power at 25 deg. c), terminal mosfet driver with zener diode gate protection (electromechanical output) diode coil suppression and terminals with 0.100 grid lea.

References

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ROHM Semiconductor, USA LLC | 1-Source Electronic Components | Mornsun Power (Mfg.)