A collection of driving technologies for power MOSFETs in switching power supplies

Power MOSFET has become the best choice for rectifier components of switch-mode power supplies (SMPS) with its outstanding advantages of low on-resistance and large load current. The emergence of dedicated MOSFET drivers has brought opportunities for optimizing SMPS controllers. Drivers integrated with SMPS controllers are only suitable for products with simple circuits and small output currents; and drive circuits built with discrete active or passive devices can neither meet the requirements for high performance nor obtain the cost advantages of dedicated monolithic driver devices. The pulse rise delay, fall delay and propagation delay of dedicated drivers are very short, and the circuit types are also very complete, which can meet the design needs of various products.

High-current MOSFET gate drivers

are optimized POL DC-DC converters for intermediate bus architecture (IBA) systems, core regulators for Intel and AMD microprocessors, high-current flat DC-DC converters, high-frequency and high-efficiency VRMs and VRDs, and synchronous rectification isolated power supplies. Applications such as these have put forward urgent demands for high-current MOSFET gate drivers. Such MOSFET gate drivers must be able to reduce switching losses and improve working efficiency. At the same time, they must have many features such as fault protection and pin compatibility to achieve more functions and higher speeds in the system.

Intersil's newly launched high-frequency 6A sink synchronous MOSFET gate drivers ISL6615 and ISL6615A can meet the above requirements. These new devices help provide higher efficiency, flexibility and more protection functions for system safety.

Taking ISL6615 as an example, it adopts a synchronous rectification buck converter topology and is a high-speed MOSFET driver specifically used to drive high and low power N-channel MOSFETs. This driver integrates Intersil's digital or analog multi-phase PWM controller to form a complete high-frequency and high-efficiency regulator. It can drive high and low gates at 4.5 V to 13.2 V. Its drive voltage allows for optimization of the flexibility required by the application, including the balance between gate charge and conduction losses. The

new driver increases gate drive current (4A for sourcing and sinking gate drive current for UGATE, 6A and 4A for sinking and sourcing current for LGATE), which can shorten gate voltage rise and fall times. This will minimize switching losses and improve efficiency, especially in high current applications with parallel power MOSFETs per phase. The

ISL6615 and ISL6615A also support 9.6V and 12V input rails. In addition, designers can choose device variants that support 3.3V PWM signals (ISL6615) or 5V PWM signals (ISL6615A). Each device has a wide input voltage operating range of 12 V to 5 V, and all devices are pin-to-pin compatible with Intersil's previous generation ISL6594D.

To provide higher system safety protection, the two products achieve this goal with multiple protections such as bootstrap capacitors to prevent overcharging, three-state PWM output safety output stage shutdown, pre-POR overvoltage protection and VCC undervoltage protection. This focus on system safety, coupled with improved flexibility and higher gate drive efficiency, helps designers maintain consistency in board design while achieving many improvements and avoiding the use of expensive low RDS(ON) MOSFETs.

In addition, the ISL6615 also features advanced adaptive zero breakdown dead time control, power-on reset (POR) function, and multi-function gate drive voltage. These all contribute to the industry's best switching efficiency without redesigning the board.

ESBT power switch reduces energy consumption, size and cost

STMicroelectronics has launched the STC03DE220HV ESBT (emitter-switched bipolar transistor) power switch, enabling design engineers to improve the energy efficiency of auxiliary switching power supplies for single-phase and three-phase applications and reduce product cost, component count and size.

The STC03DE220HV is the first product in the new ST ESBT series with a rated breakdown voltage of 2200V. The new product allows designers to use a single power switch flyback topology in universal input converters with supply voltages from 90V AC to 690V AC. Using a common hardware platform, combined with a suitable controller such as the L6565, ST's complete ESBT product allows designers to develop quasi-resonant converters with a maximum power of up to 250W. With

high-efficiency switching frequencies up to 150kHz and a maximum current rating of 3A, the STC03DE220HV can be used in a variety of auxiliary switching power supplies, including commercial meters, induction motor inverters, welding equipment, and uninterruptible power supplies (UPS). The reinforced TO247-4L package is another highlight of the new product, and the 8.9mm creepage distance exceeds the insulation requirements of IEC664-1 at a maximum working voltage of 2200V.

Combining the three advantages of low on-state losses, high switching frequencies from traditional MOSFETs, and simple gate drive design, the STC03DE220HV optimizes standard bipolar transistors and high-voltage MOSFETs using ESBT technology. From collector to source, the STC03DE220HV achieves an equivalent on-resistance of 0.33 ohms while also achieving a maximum switching frequency of 150kHz, which allows the design to use smaller filters. In addition, the entire die size is smaller than high-voltage MOSFETs of the same voltage level, which saves costs. The square safe operating area (SOA) of the ESBT also helps simplify power supply design and ensures reliable performance in various environments. ZXGD3000 bipolar gate driver can inject 9A current

Zetex Semiconductors has launched the new ZXGD3000 bipolar gate driver series for MOSFETs and IGBTs in switching power supplies and motor drives. The low-cost ZXGD3000 series can inject up to 9A of current, and the gate capacitance is charged and discharged faster than the gate driver IC, which helps to speed up switching time and improve circuit efficiency.

The series includes 4 high-speed non-reversing gate drivers with a supply voltage range of 12V to 40V. Its fast-switching emitter follower configuration achieves a propagation delay of less than 2ns and a rise/fall time of approximately 10ns, effectively improving control over MOSFET switching performance. The ZXGD3000 can also prevent latching and eliminate breakdown, thereby improving circuit reliability and EMI performance.

The ZXGD3000 gate driver series uses a 6-lead SOT23 package to reduce the number of components and increase power density. The high current gain and low input current requirements of these devices can be directly connected to low-power controller ICs without the need for buffer circuits.

The device uses independent inflow and outflow output pins, giving designers the flexibility to independently control gate rise and fall times. The pin distribution of the SOT23-6 package has been optimized to greatly simplify printed circuit board layout and minimize trace inductance; the pass-through design method used can place the input and output terminals on two opposite sides of the device.

High-speed single/dual-channel MOSFET driver

Maxim introduces the MAX15024/MAX15025 high-speed, single- and dual-channel MOSFET drivers in a 3mm x 3mm, thermally enhanced TDFN package. The MAX15024 is a single-channel gate driver capable of sinking 8A peak current and sourcing 4A peak current. The MAX15025 is a dual-channel gate driver capable of sinking and sourcing up to 4A peak current. The channel-to-channel propagation delay matching of both devices is typically 2ns, and the device-to-device propagation delay matching is typically less than 17ns. The devices include an adjustable LDO for gate drive amplitude control and optimization. The MAX15024/MAX15025 are ideal for power MOSFET switching, motor control, and compact, high-frequency switching power supplies.

The MAX15024/MAX15025 operates from a 4.5V to 28V supply voltage and can withstand transients up to 30V. In addition, the inverting and non-inverting logic inputs of the devices operate at 22V, independent of the VCC supply voltage. The device contains a logic protection circuit to prevent internal shoot-through current during output state changes, and the logic circuit supports CMOS or TTL logic level inputs. The

MAX15024/MAX15025 operates over the -40℃ to +125℃ automotive temperature range. Available in a 3mm x 3mm, 10-pin TDFN package with an exposed pad, it can dissipate up to 2W at an ambient temperature of +70℃.

Solid 600V three-phase gate driver IC

IR has introduced a solid 600V three-phase gate driver IC, which is mainly used in high, medium and low voltage motor drive applications including home appliances, industrial drives, micro inverter drives and electric vehicle drives for permanent magnet motor drives.

The IRS26310DJPbF integrates power MOSFET and IGBT gate drivers with three high-side and three low-side reference output channels, providing 200mA/350mA drive current at up to 20V MOS gate drive capability and a maximum operating voltage of 600V. The new IC incorporates an integrated bootstrap diode to provide comprehensive protection functions, including an improved negative voltage spike (Vs) immunity circuit to prevent catastrophic events in the system under high current switching or short circuit conditions, achieving a higher level of durability and reliability. It also integrates an advanced input filter to suppress noise and reduce distortion, thereby improving system performance. The

new device's specific application protection functions include DC bus detection with overvoltage protection and zero vector braking function for permanent magnet motor drive. The current cut-off function derived from the external current sense resistor can terminate all six outputs, and has a trigger function to terminate six outputs simultaneously.

The output driver of the device has a high pulse current buffer stage to minimize the driver transconductance. The propagation delay is also suitable for simplifying high-frequency applications.

The new device uses IR's advanced high-voltage IC (HVIC) process, integrating a new generation of high-voltage level conversion and termination technology to provide excellent electrical overstress protection and higher field reliability. In addition to over-current and over-temperature detection inputs, the IRS26310D also has under-voltage lockout protection, integrated dead time protection, breakdown protection, shutdown input, error reporting and other functions, and is compatible with 3.3V input logic.