Fast latching switches
View Patent ↗Devices, methods and techniques related to ultrafast latching switches are disclosed. In one example aspect, a device includes a photoconductive switch and a non-mechanical latching switch configured to maintain a state after the state is activated. The non-mechanical latching switch is coupled to the photoconductive switch. The non-mechanical latching switch is configured to be triggered to switch to an opposite state upon an activation of the photoconductive switch.
1 . A device, comprising:
a photoconductive switch including a wide bandgap material positioned to receive an optical signal, the wide bandgap material doped with a dopant to form a mid-gap state within a bandgap of the wide bandgap material to achieve an enhanced rise time when excited by the optical signal; and
a non-mechanical latching switch configured to maintain a state after the state is activated, the photoconductive switch coupled to the non-mechanical latching switch,
wherein the non-mechanical latching switch is configured to be triggered to switch to an opposite state upon an activation of the photoconductive switch.
2 . The device of claim 1 , wherein, upon the activation of the photoconductive switch, the non-mechanical latching switch is triggered to turn on.
3 . The device of claim 1 , wherein, upon the activation of the photoconductive switch, the non-mechanical latching switch is triggered to turn off.
4 . The device of claim 1 , wherein the mid-gap state within the bandgap of the wide bandgap material enables a rise time of less than 10 ns upon excitation of the wide bandgap material by the pulsed signal.
5 . The device of claim 1 , comprising:
a passive network coupled to the photoconductive switch and to the non-mechanical latching switch,
wherein the passive network and the photoconductive switch are positioned in a series configuration with respect to each other, and
wherein the passive network is operable, upon the activation of the photoconductive switch, to provide a counter-pulse or a short to the non-mechanical latching switch to produce a zero current condition.
6 . The device of claim 5 , wherein:
a first node of the photoconductive switch is coupled to a third node of the non-mechanical latching switch,
a second node of the photoconductive switch is coupled to a first node of the passive network,
a second node of the passive network is coupled to a second node of the non-mechanical latching switch, and
a current flow through the non-mechanical latching switch is conducted between a first node and the second node of the non-mechanical latching switch.
7 . The device of claim 5 , wherein:
a first node of the photoconductive switch is coupled to a first node of the non-mechanical latching switch,
a second node of the photoconductive switch is coupled to a first node of the passive network,
a second node of the passive network is coupled to a second node of the non-mechanical latching switch, and
a current flow through the non-mechanical latching switch is conducted between the first node and the second node of the non-mechanical latching switch.
8 . The device of claim 5 , wherein the passive network comprises a voltage source.
9 . The device of claim 5 , wherein the passive network comprises a combination of resistors, capacitors, and/or inductors.
10 . The device of claim 1 , wherein the non-mechanical latching switch comprises a thyristor.
11 . The device of claim 10 , wherein the thyristor comprises a gate, and wherein:
a second photoconductive switch is coupled to the gate of the thyristor configured to activate the thyristor,
a first node of the photoconductive switch is coupled to the gate of the thyristor,
a second node of the photoconductive switch is coupled to a first node of a passive network,
a second node of the passive network is coupled to a cathode of the thyristor.
12 . The device of claim 11 , wherein the device is configured to operation at a switching frequency around 100,000 KHz.
13 . The device of claim 1 , wherein the non-mechanical latching switch comprises at least one of: a junction or bulk conduction device, a silicon-controlled rectifier, or an avalanche photoconductive semiconductor switch.
14 . A method for switching a non-mechanical latching device, comprising:
activating the non-mechanical latching device to operate in a first state, wherein the non-mechanical latching device is configured to maintain the first state after the first state is activated, wherein the non-mechanical latching device is coupled to a photoconductive switch in a circuit; and
switching the non-mechanical latching device to a second state by providing an optical signal to the photoconductive switch to activate the photoconductive switch, wherein the photoconductive switch has a wide bandgap material, the wide bandgap material being doped with a dopant to create a mid-gap state within a bandgap of the wide bandgap material to achieve an enhanced rise time when the photoconductive switch is excited by the optical signal.
15 . The method of claim 14 , wherein the optical signal comprises a pulsed optical signal, and wherein the wide bandgap material is positioned to receive the pulsed signal from the light source, and the wide bandgap material achieves a rise time that is less than 20 ns upon excitation of the wide bandgap material by the pulsed optical signal.
16 . The method of claim 14 , further comprising:
supplying, by a passive network that is coupled to the photoconductive switch and the non-mechanical latching device, a counter-pulse or a short to the non-mechanical latching device upon activating of the photoconductive switch.
17 . The method of claim 16 , wherein the passive network comprises a voltage source or a combination of resistors, capacitors, and/or inductors.
18 . The method of claim 14 , wherein the non-mechanical latching device comprises at least one of: a junction or bulk conduction device, a silicon-controlled rectifier, or an avalanche photoconductive semiconductor switch.
19 . The method of claim 14 , wherein the non-mechanical latching device comprises a thyristor that comprises a gate, and wherein:
a second photoconductive switch is coupled to the gate of the thyristor configured to activate the thyristor,
a first node of the photoconductive switch is coupled to the gate of the thyristor,
a second node of the photoconductive switch is coupled to a first node of a passive network, and
a second node of the passive network is coupled to a cathode of the thyristor.
20 . The method of claim 14 , wherein switching of the latching device between the first state and the second state is completed within 10 ns.