公开(公告)号：US20220360259A1

公开(公告)日：2022-11-10

申请号：US17308423

申请日：2021-05-05

Applicant: GaN Systems Inc.

Inventor： Ruoyu HOU ,  Juncheng LU ,  Larry SPAZIANI

IPC: H03K17/0812 ,  H03K17/16

Abstract: An active gate voltage control circuit for a gate driver of a power semiconductor switching device comprising a power semiconductor transistor, such as a GaN HEMT, provides active gate voltage control comprising current burst mode operation and protection mode operation. The gate-source turn-on voltage Vgs(on) is increased in burst mode operation, to allow for a temporary increase of saturation current. In protection mode operation, a multi-stage turn-off may be implemented, comprising reducing Vgs(on) to implement fast soft turn-off, followed by full turn-off to bring Vgs(on) below threshold voltage, to reduce switching transients such as Vds spikes. Circuits of example embodiments provide for burst mode operation for enhanced saturation current, to increase robustness of enhancement mode GaN power switching devices, e.g. under overcurrent and short circuit conditions, or to provide active gate voltage control which adjusts dynamically to specific operating conditions or events.

公开(公告)号：US20230282540A1

公开(公告)日：2023-09-07

申请号：US17979970

申请日：2022-11-03

Applicant: GaN Systems Inc.

Inventor： Ruoyu HOU ,  Juncheng LU ,  Andrew DICKSON

IPC: H01L23/367 ,  H01L23/373 ,  H01L25/07 ,  H01L29/20

CPC classification number: H01L23/3672 ,  H01L23/3735 ,  H01L23/3731 ,  H01L25/072 ,  H01L29/2003

Abstract: A multi-zone substrate for a power stage assembly comprising at least one bottom-cooled semiconductor power switching device and driver components, for integration on a common substrate. A first zone provides electrical connections and a thermal pad for mounting at least one bottom-cooled semiconductor switching device, the first zone comprising dielectric and conductive layers which provide a power substrate optimized for thermal performance. A second zone provides electrical connections for mounting driver components, the second zone comprising dielectric and conductive layers providing a driver substrate optimized for electrical performance. For example, the first zone comprises a single layer metal interconnect structure with a first thermal resistance, the second zone comprises a multi-layer metal interconnect structure with a second thermal resistance, the first thermal resistance being less than the second thermal resistance. The power stage assembly may comprise a multi-zone substrate configured for a single switch, half-bridge or full-bridge switch topology.

公开(公告)号：US20240306348A1

公开(公告)日：2024-09-12

申请号：US18120046

申请日：2023-03-10

Applicant: GaN Systems Inc.

Inventor： Ruoyu HOU ,  Juncheng LU

IPC: H05K7/20 ,  H01L23/367 ,  H05K1/02 ,  H05K1/18

CPC classification number: H05K7/20409 ,  H01L23/3672 ,  H05K1/0216 ,  H05K1/185 ,  H05K2201/066 ,  H05K2201/10166

Abstract: A power stage assembly for improved thermal dissipation and EMC for top-cooled semiconductor power switching devices, e.g. high voltage, high current lateral GaN power transistors in embedded die packages. The power switching devices are mounted on a PCB substrate, with electrical connections between a bottom side of each device package and the PCB. Each device package has a thermal pad on the top-side. A heat-spreader is secured in thermal contact with the thermal pads of each device, and a heatsink is in thermal contact with the heat-spreader. The heat-spreader is a multilayer structure comprising: a thermally conductive metal substrate layer in contact with the heatsink; a conductive layer providing an EMC layer which is connected to power ground; a conductive layer defining large area thermal pads in thermal contact with thermal pads of each die; and dielectric material electrically isolating conductive layers of the heat-spreader.

公开(公告)号：US20230402342A1

公开(公告)日：2023-12-14

申请号：US18094477

申请日：2023-01-09

Applicant: GaN Systems Inc.

Inventor： Di CHEN ,  Juncheng LU ,  Ahmad MIZAN ,  Ruoyu HOU ,  Abhinandan DIXIT

IPC: H01L23/367 ,  H01L29/16 ,  H01L29/20 ,  H01L29/66

CPC classification number: H01L23/3672 ,  H01L29/1608 ,  H01L29/2003 ,  H01L29/66462

Abstract: Embedded die packaging for high voltage, high temperature operation of power semiconductor switching devices is disclosed, wherein a power semiconductor die is embedded in laminated body comprising a layer stack of a plurality of dielectric layers and electrically conductive layers, and wherein a first thermal pad on one side of the package and a second thermal pad on an opposite side of the package provides for dual-side cooling. Example embodiments of the dual-side cooled package may be based on a bottom-side cooled layup with a primary bottom-side thermal pad and a secondary top-side thermal pad, or a top-side cooled layup with primary top-side thermal pad and a secondary bottom side thermal pad, using layups with or without a leadframe. For example, the power semiconductor switching device comprises a GaN power transistor, such as a GaN HEMT rated for operation at ≥100V or ≥600V, for switching tens or hundreds of Amps.

公开(公告)号：US20220182048A1

公开(公告)日：2022-06-09

申请号：US17533365

申请日：2021-11-23

Applicant: GaN Systems Inc.

Inventor： Xuechao LIU ,  Ruoyu HOU

IPC: H03K17/082 ,  H02M1/00 ,  H02M1/32 ,  H02M3/335 ,  H01L29/20

Abstract: High accuracy current sense circuitry for power switching devices comprising GaN power transistors provides for current feedback functions, e.g. current loop control, over-current protection (OCP) and short-circuit protection (SCP). The current sense circuitry comprises a current mirror sense GaN transistor (Sense_GaN) and a power GaN transistor (Power_GaN) and a sampling circuit. The sampling circuit comprises first and second stage operational amplifiers to provide fast response and improved current sense accuracy, e.g. better than 1%, over a range of junction temperatures Tj. The Sense_GaN, Power_GaN and first stage operational amplifier have a common ground referenced to a Kelvin Source of the Power_GaN, so that the Sense_GaN and Power_GaN operate with the same gate-to-source voltage Vgs, to provide an accurate current ratio. Applications include current sensing for switching mode power supplies that need high speed and lossless current sense for current protection and feedback.