Use of conducting fluid in printed circuits

An apparatus for toggling circuits includes a plurality of parallel channels each having a first end and a second end, a plurality of ports transverse to the plurality of parallel channels, wherein each port has a plurality of valves corresponding to the plurality of parallel channels, wherein each valve selectively opens and closes in response to an input and wherein opening a valve fills a portion of a port with a conducting fluid. The apparatus also includes a controller communicatively coupled to the input of each valve and configured to complete an electric circuit between the first end of the parallel channel and the port corresponding to the valve when the controller opens the valve. A method executed by a computer and a corresponding computer program product are also disclosed herein.

BACKGROUND OF THE INVENTION

The present invention relates generally to printed circuits, and more specifically, to the use of conducting fluids to toggle individual electric circuits.

In the field of printed circuits, control of the connectivity of individual circuits is difficult. One reason for this is that printed circuits have grown increasingly complicated as the complexity of printed circuits increases. One challenge is to maintain control over each individual circuit despite the number of circuits increasing and the dimensions of each circuit decreasing.

SUMMARY

As disclosed herein, an apparatus for toggling circuits includes a plurality of parallel channels each having a first end and a second end, a plurality of ports transverse to the plurality of parallel channels, wherein each port has a plurality of valves corresponding to the plurality of parallel channels, wherein each valve selectively opens and closes in response to an input and wherein opening a valve fills a portion of a port with a conducting fluid. The apparatus also includes a controller communicatively coupled to the input of each valve and configured to complete an electric circuit between the first end of the parallel channel and the port corresponding to the valve when the controller opens the valve. A method executed by a computer and a corresponding computer program product are also disclosed herein.

DETAILED DESCRIPTION

Embodiments of the present invention relate generally to printed circuits, and more specifically, to the use of conducting fluids to toggle individual electric circuits. Insertion of conducting fluid into a microchannel may be used to complete an electric circuit, just as removing the conducting fluid may break the circuit. Thus, selectively controlling the presence/absence of conducting fluid in microchannels may provide a means of controlling the activity of circuits on a printed circuit board. Furthermore, use of conducting fluids in printed circuits may enable circuits to be highly compact while also possessing redundancies that make the circuits tolerant to damage.

It should be noted that references throughout this specification to features, advantages, or similar language herein do not imply that all of the features and advantages that may be realized with the embodiments disclosed herein should be, or are in, any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features, advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.

These features and advantages will become more fully apparent from the following drawings, description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. The present invention will now be described in detail with reference to the figures.

FIGS. 1A and 1Bdepict examples of one embodiment of a microvalve in accordance with the present invention. As depicted, microvalve100includes a conduction path110, a microvalve120, a port130, and a conducting fluid140.FIG. 1Adepicts a closed microvalve120that prevents the conducting fluid140from entering the port130, whereasFIG. 1Bdepicts an open microvalve120, which may enable the conducting fluid140to enter port130.

Conduction path110may be a conductive trace of a circuit. In some embodiments, microvalve100is one of many microvalves positioned serially along a portion of conduction path110. Conduction path110may be made of any conducting material used in printed circuitry, such as copper, silver, gold, aluminum, alloys thereof, graphene, and the like. The printed circuitry may be printed on a rigid or flexible printed circuit medium.

Microvalve120may be a microstructure acting as a valve that, when closed, substantially impedes the flow of conducting fluid140. Microvalve120may be an active microvalve or passive microvalve. Active microvalves may include mechanical, non-mechanical, and external microvalves. Mechanical microvalves in turn may include magnetic, electric, piezoelectric, thermal, and bistable microvalves. Non-mechanical microvalves may include electrochemical, phase change, and rheological microvalves. External microvalves may include modular and pneumatic microvalves. In embodiments where microvalve120is a passive microvalve, microvalve120is either a mechanical check-valve microvalve, or a capillary microvalve.

Port130may be a chamber or cavity that is empty when microvalve120is closed, but fills with conducting fluid140when microvalve120opens. When filled with conducting fluid140, port130may complete a circuit in the conduction path110, enabling electrons to flow from one end of conduction path110, through port130, and into the other end of conduction path110, as depicted inFIG. 1B. When conducting fluid140is removed from port130and microvalve120is closed (as depicted inFIG. 1A), port130may act as an insulator that disrupts electron flow through conduction path110.

Conducting fluid140may be any sort of fluid capable of bridging the gap in conduction path110so that electrons can pass through port130. Conducting fluid140may be selected based on one or several fluid properties, such as density, viscosity, electric conductivity, and thermal conductivity. Conducting fluid140may also be selected based on its hydraulic friction factor formed at the surfaces of the conduction path110, microvalve120, and/or port130. In some embodiments, conducting fluid140is selected based on its Reynolds number achieved when conducting fluid140flows into or out of port130. Conducting fluid140may include metals, such as mercury or gallium, that are liquid at temperatures associated with computing. In some embodiments, conducting fluid140includes any metallic or non-metallic element, compound, mixture, suspension, solution, or other combination that is capable of exhibiting fluid properties and conducting electrons through port130. Conducting fluid140may be a conductive ink. In some embodiments, conducting fluid140is stored in a reservoir such as one of the channels230A-230C depicted inFIGS. 2A-2B.

FIGS. 2A-2Bdepict examples of embodiments of controllable circuitry200in accordance with the present invention.FIG. 2Ais a side view andFIG. 2Bis a top view. As depicted, controllable circuitry200includes channel ends210A and210B, circuit terminals220A-220D, channels230A-230C, ports240A-240D, and microvalves250A-250L, as well as controller260and controller circuits270A-270C. In the depicted embodiment, there are three channels230A-230C, which corresponds to a redundancy factor of three for controlling each circuit.

FIG. 2Ais a side view of controllable circuitry200to illustrate the relation between the channels230A-230C, microvalves250A-250C, port240A and circuit terminal220A. The various dimensions of controllable circuitry200may be exaggerated for clarity. Conducting fluid may be stored in each of the channels230A-230C. In some embodiments, the conducting fluid is pumped into or out of channels230A-230C on demand. When a microvalve opens, conducting fluid flows from a channel through the microvalve and to the port, which enables electricity to flow to circuit terminal220A and activate a circuit. For example, when microvalve250B opens, conducting fluid flows from230B to contact port240A, completing a circuit. When the circuit is to be deactivated, the conducting fluid may be removed from the opened microvalve, at which point the microvalve may close. In some embodiments, the conducting fluid is removed via application of a negative pressure. The embodiment depicted inFIG. 2Amay be considered to have a redundancy factor of three, as the circuit can be activated by opening either microvalve250A,250B, or250C.

Turning toFIG. 2B, controllable circuitry200has three parallel channels,230A-230C, which are bounded by channel ends210A and210B. Channels230A-230C may be capable of housing a conducting fluid such as conducting fluid140as described inFIGS. 1Aand1B. In some embodiments, channel ends210A-210B and walls of channels230A-230C act as boundaries that confine the conducting fluid within one or more of the channels230A-230C.

Circuits may be activated or deactivated by completing or breaking an electrical connection between channel end210A and one of the circuit terminals, such as circuit terminal210A. In one embodiment, a circuit is activated when a microvalve opens to allow conducting fluid to complete a circuit in a port, which electrically connects channel end210A with a circuit terminal corresponding to the open microvalve and port. For example, when microvalve250A opens, conducting fluid that was confined to channel230A may flow into port240A, which completes an electrical connection between channel end210A and circuit terminal220A.

The controllable circuitry200thus may be controlled by selectively opening/closing one or more of the microvalves. If, for example, microvalve250B is damaged, then the circuit spanning channel end210A to circuit terminal220A may still be controllable by opening/closing either microvalve250A or250C. Thus, because there are three channels230A-230C in the depicted example, each of the four circuits in the depicted example has a redundancy factor of three. Ports240A-240D may contain a conductor that enables electricity to flow from channel end210A through a conducting fluid in a channel (such as channel230C), to an open microvalve (such as microvalve250H) in a port (such as port240C), and then to the circuit terminal associated with that port (such as circuit terminal220C). In some embodiments, there are more or fewer channels, as a higher number of channels may increase cost and/or scale up the redundancy of controllable circuitry200.

Controller260may include any sort of digital controller capable of signaling the microvalves250A-250L with instructions to open and/or close. Controller260may open and close each microvalve250A-250L independently using controller circuits270A-270C. In some embodiments, controller260itself receives instructions from another microprocessor. Controller260may communicate independently with each microvalve250A-250L via one of the controller circuits270A-270C. For example, in order to open microvalves250B and250E and to close microvalve250J, controller signals microvalves250B and250E to open via controller circuit270B, and signals microvalve250J to close via controller circuit270A. When controller260signals a microvalve to close, the microvalve may pump the conducting fluid out of the microvalve and its corresponding port before closing, which may ensure that the electrical circuit is severed. When conducting fluid is not being used by a port or microvalve to complete a circuit, the conducting fluid may be stored in a reservoir such as channels230A-230C.

FIG. 3is a flow chart depicting one embodiment of a circuit toggling method in accordance with the present invention. As depicted, circuit toggling method300includes receiving (310) instructions, opening (320) a valve, and closing (330) a valve. The circuit toggling method300may thus be used to selectively activate or deactivate a particular circuit, such as the circuits depicted inFIGS. 2A-2B.

Receiving (310) instructions to open a valve may include a microvalve receiving a signal to open. In some embodiments, the microvalve receives the signal from a controller, such as controller260depicted inFIG. 2B. Opening (320) the valve may occur in response to receiving (310) instructions to open the valve. When the microvalve opens, a conducting fluid that the microvalve was previously holding back may enter a space such that an electrical circuit is completed. In some embodiments, the conducting fluid bridges an otherwise insulator gap, enabling electrons to flow through the fluid and across the gap.

Closing (330) the valve and breaking the circuit may include removing the conducting fluid, closing the valve, and breaking the electrical circuit formed as a result of valve opening operation320. In some embodiments, the conducting fluid is returned to a storage reservoir, such as one of the channels230A-230C depicted inFIGS. 2A-2B. Once the conducting fluid is removed and the valve is closed, the electrical circuit is broken and thus, the circuit is deactivated. The valve closing operation330may occur in response to a signal received from a controller. By repeating circuit toggling method300individual circuits may be selectively activated and deactivated.

FIG. 4is a block diagram depicting components of a computer400suitable for executing the methods disclosed herein. It should be appreciated thatFIG. 4provides only an illustration of one embodiment and does not imply any limitations with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environment may be made.

Memory406and persistent storage408are computer readable storage media. In the depicted embodiment, memory406includes random access memory (RAM)416and cache memory418. In general, memory406can include any suitable volatile or non-volatile computer readable storage media.

One or more programs may be stored in persistent storage408for execution by one or more of the respective computer processors404via one or more memories of memory406. The persistent storage408may be a magnetic hard disk drive, a solid state hard drive, a semiconductor storage device, read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, or any other computer readable storage media that is capable of storing program instructions or digital information.

Communications unit412, in these examples, provides for communications with other data processing systems or devices. In these examples, communications unit412includes one or more network interface cards. Communications unit412may provide communications through the use of either or both physical and wireless communications links.

I/O interface(s)414allows for input and output of data with other devices that may be connected to computer400. For example, I/O interface414may provide a connection to external devices420such as a keyboard, keypad, a touch screen, and/or some other suitable input device. External devices420can also include portable computer readable storage media such as, for example, thumb drives, portable optical or magnetic disks, and memory cards.

Software and data used to practice embodiments of the present invention can be stored on such portable computer readable storage media and can be loaded onto persistent storage408via I/O interface(s)414. I/O interface(s)414may also connect to a display422. Display422provides a mechanism to display data to a user and may be, for example, a computer monitor.