Cambridge Gan Devices Limited

Sheung Wai Fung

Florin Udrea

Loizos Efthymiou

Martin Arnold

John William Findlay

Giorgia Longobardi

Zahid Ansari

Tara Vishin

Wai Hon Ng

A semiconductor switch comprising a first main terminal, a second main terminal, and a control terminal, the semiconductor switch further comprising: a III-nitride high-electron-mobility transistor (HEMT), the III-nitride HEMT comprising a first source terminal, a first drain terminal, and a first gate terminal; a first interface circuit operatively connected to the control terminal and to the first gate terminal; and a short-circuit detection circuit operatively connected to the first drain terminal and the first source terminal, the short-circuit detection circuit being configured to: sense a short-circuit across the first drain terminal and the first source terminal; and transmit a short-circuit detection signal to the first interface circuit, the first interface circuit being configured, upon receipt of the short-circuit detection signal, to cause the III-nitride HEMT to turn off, and/or to cause a voltage across the first gate terminal to be reduced.

Semiconductor switch comprising a short-circuit detection circuit

We describe a smart high voltage/power III-nitride semiconductor based diode or rectifier comprising first and second terminals, and further comprising an active device (e.g. a transistor such as a GaN HEMT transistor), a sensing device (e.g. a sensing diode/transistor), a sensing load (e.g. a resistor), wherein the smart high voltage/power III-nitride semiconductor based diode or rectifier is configured to output a sensing signal corresponding a current through the sensing device and/or a voltage drop across the sensing load, wherein the sensing signal is indicative of a current flowing between the first and second terminal when a bias is applied between the first and second terminals.

III-nitride power semiconductor based heterojunction diode

A III-nitride power semiconductor based heterojunction device comprising a substrate, a first terminal, a second terminal, a control terminal configured to receive an input switching signal during an active mode of operation and to not receive the input switching signal during a stand-by mode of operation, and an active heterojunction transistor formed on the substrate. The device further comprises a stand-by signal generation circuit configured to generate a stand-by signal when the input switching signal to the control terminal has not been detected for a set period of time, at least one Miller clamp transistor and driving circuitry associated with the at least one Miller clamp transistor, a voltage regulator circuit configured to provide at least a low power consumption output and a high power consumption output, wherein the low power consumption output is enabled at least during the stand-by mode of operation and the high power consumption output is disabled by the stand-by signal during the stand-by mode of operation, and a rail voltage terminal configured to provide an input to the voltage regulator circuit. The low power consumption output is provided to the driving circuitry of the at least one Miller clamp transistor to thereby maintain the at least one Miller clamp transistor in an on-state during the stand-by mode of operation, and the low power consumption output is provided to the stand-by signal generation circuit to thereby power up the stand-by signal generation circuit.

Stand-by circuit

A heterojunction device having at least three terminals, the at least three terminals comprising a high voltage terminal, a low voltage terminal and a control terminal. The heterojunction device further comprises at least one main power heterojunction transistor, an auxiliary gate circuit comprising at least one first low-voltage heterojunction transistor, a pull-down circuit comprising a capacitor and a charging path for the capacitor. The heterojunction device further comprises at least one monolithically integrated component, wherein the capacitor is configured to provide an internal rail voltage for the at least one monolithically integrated component.

Power semiconductor device with an auxiliary gate structure

The present disclosure relates to an edge detection circuit configured to receive an input signal comprising one or more falling or falling edges and provide an output signal comprising pulses or spikes corresponding to the one or more rising or falling edges. The edge detection circuit comprises a passive differentiator circuit configured to receive an input and provide a differentiator output signal that that is proportional to the rate of change of the input, and a comparator circuit operably connected to a voltage source. The comparator circuit is configured to receive the differentiator output signal, compare the differentiator output signal to a threshold voltage; and output a pulse or spike signal based on the comparison to the threshold voltage.

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Cambridge, United Kingdom

Sheung Wai Fung