STAR2040

Description

STAR2040 is a CMOS cascode driver circuit designed for use with high-current GaN (or SiC) power FET devices. It can be operated with 20 A of current, with a typical on-resistance of <15 milliohms. In a typical usage scenario, the driver can achieve a switching frequency as high as 2 MHz. This permits the use of small external passive components in switching converter applications, and hence a low BOM. The driver is implemented in a standard 5-V CMOS process, without the need for any special high-voltage devices. It requires a single 5-V power supply (VDD).

The driver state is controlled by a differential pair (INP and INM) of 5-V CMOS logic signals; this signalling scheme provides rejection of common-mode noise. Due to the on-chip pre-driver, the drive-current requirement for the INP and INM pins is small. STAR2040 incorporates a variety of monitoring and safety features, such as: (1) an integrated protection diode for the drain node; (2) an integrated analog temperature sensor; (3) a tunable rise/fall-time control circuit; and (4) monitoring capability for the drain, gate, and source nodes. Because of its high current capability, low on-resistance, and high switching frequency, STAR2040 is ideally suited for high-current, high-voltage switching converter applications that require the use of GaN (or SiC) devices. This potentially includes applications such as electric vehicles, high-current appliances, and power supplies for laptop computers.

Features

• Current handling: up to 20 A

• Typical on-resistance: <15 milliohms (@ 20 A)

• 2-MHz switching capability

  • Permits use of smaller external components

• Implemented using commodity 5-V CMOS process

  • No high-voltage process required

• Single 5-V power supply required

  • Current draw: 1.2 A peak, 24 mA average (for 2-MHz switching)

• 5-V CMOS logic levels used for input control signals

  • Differential signalling used (for better common-mode rejection in noisy environments)

  • Typical input current < 1.5 mA peak (for 4-ns rise/fall time)

  • Output rise/fall time is insensitive to input rise/fall time

• Additional features: – Built-in protection diode keeps drain node safe – Built-in analog temperature sensor – Rise/fall-time control at gate (set by optional external resistor) – Analog monitoring of drain, gate, source nodes

• Die size: 4.05 mm x 4.05 mm – Drain connections designed for vertical packaging with GaN device – Source connections can be made with TSVs, for completely vertical current flow

Applications

• High-current, high-voltage dc-dc converters

  • Electric vehicles

• High-current ac-dc converters

  • High-current appliances

  • Power supplies for laptop computers