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A fluid flow sensor that utilizes hot-wire anemometry and is a small, light weight, cost effective, easily manufactureable, and low power consuming device. The fluid flow sensor operates by exposing a hot wire loop to a fluid stream such that the amount of heat lost to fluid convection is a function

A fluid flow sensor that utilizes hot-wire anemometry and is a small, light weight, cost effective, easily manufactureable, and low power consuming device. The fluid flow sensor operates by exposing a hot wire loop to a fluid stream such that the amount of heat lost to fluid convection is a function of one or more fluid-related parameters (e.g., fluid speed, fluid type, fluid density, etc.). The heat loss affects the resistance in the wire loop, which can then be used to estimate the fluid speed or other fluid-related parameter. According to an exemplary embodiment, the fluid flow sensor includes one or more wire loops that are made from pre-formed wires and are wire bonded, micro-welded or otherwise non-monolithically attached to a substrate that may or may not include embedded sensor circuitry.

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1. A fluid flow sensor, comprising: a substrate;at least one wire connection mounted on the substrate; andat least one wire loop attached to the substrate via the wire connection, wherein the wire loop is made from a pre-formed wire that is non-monolithically attached to the substrate as a sensing e

1. A fluid flow sensor, comprising: a substrate;at least one wire connection mounted on the substrate; andat least one wire loop attached to the substrate via the wire connection, wherein the wire loop is made from a pre-formed wire that is non-monolithically attached to the substrate as a sensing element. 2. The fluid flow sensor of claim 1, wherein the wire loop includes at least one wire material selected from the group consisting of: platinum (Pt), aluminum (Al), gold (Au), tungsten (W), iridium (Ir), copper (Cu), silver (Ag), paladium (Pd), silicon (Si), chromium (Cr), or an alloy thereof. 3. The fluid flow sensor of claim 1, wherein the wire loop has a diameter from about 1 μm to 500 μm and a length from about 0.5 mm to 200 mm. 4. The fluid flow sensor of claim 1, wherein the wire loop is a pre-formed wire and includes at least one end that is wire bonded to the substrate via a bonding pad located on a surface of the substrate. 5. The fluid flow sensor of claim 1, wherein the wire loop is a pre-formed wire and includes at least one end that is micro-welded to the substrate via a weld located on a surface of the substrate. 6. The fluid flow sensor of claim 1, wherein the wire loop is a pre-formed wire and includes a first end attached to the substrate, a second end attached to the substrate, and an intervening body portion that extends between the first and second ends and extends away from a surface of the substrate. 7. The fluid flow sensor of claim 6, wherein the intervening body portion includes a single arch located between the first and second ends. 8. The fluid flow sensor of claim 6, wherein the intervening body portion includes a plurality of coils or bent sections located between the first and second ends. 9. The fluid flow sensor of claim 1, wherein at least one wire connection is elevated or spaced from a surface of the substrate so that the wire loop is mounted on the substrate at an elevated or offset position. 10. The fluid flow sensor of claim 1, wherein the substrate is made from a semiconducting material and includes embedded circuitry that is monolithically integrated into the substrate. 11. The fluid flow sensor of claim 1, wherein the substrate is a printed circuit board (PCB) or a flex board and includes embedded circuitry that is attached to a surface of the substrate. 12. The fluid flow sensor of claim 1, wherein the substrate includes a generally planar surface to which first and second ends of the wire loop are attached. 13. The fluid flow sensor of claim 1, wherein the substrate includes a generally non-planar surface to which first and second ends of the wire loop are attached, and the non-planar surface includes a recess located between the first and second ends so that the wire loop extends over the recess. 14. The fluid flow sensor of claim 1, comprising a single wire loop that is attached to and extends away from the substrate. 15. The fluid flow sensor of claim 1, comprising a plurality of wire loops, wherein at least one wire loop differs from another wire loop in terms of its shape, height, or wire material so that different types of wire loops are attached to the same substrate. 16. The fluid flow sensor of claim 1, comprising a plurality of wire loops arranged in a one-dimensional array, wherein the wire loops are generally aligned in a line. 17. The fluid flow sensor of claim 1, comprising a plurality of wire loops arranged in a two-dimensional array or pattern. 18. The fluid flow sensor of claim 17, wherein the two-dimensional array or pattern is generally configured according to a grid-like formation that includes columns and rows. 19. The fluid flow sensor of claim 17, wherein the two-dimensional array or pattern is generally configured according to a star- or circular-shaped pattern. 20. A sensor assembly, comprising: the fluid flow sensor of claim 1;sensor circuitry electrically connected to the fluid flow sensor; anda housing at least partially surrounding the sensor circuitry, wherein the fluid flow sensor provides sensor output to the sensor circuitry. 21. A fluid flow sensor, comprising: a substrate having embedded sensor circuitry;at least one wire connection mounted on the substrate; andat least one wire loop wire bonded to the substrate via the wire connection, wherein the wire loop is a pre-formed bond wire that is wire bonded to the substrate so that it extends away from the substrate and acts as a sensing element. 22. The fluid flow sensor of claim 21, wherein the substrate with the embedded sensor circuitry is either an integrated circuit (IC) or an IC substrate and the wire loop is directly wire bonded to the IC or the IC substrate. 23. The fluid flow sensor of claim 21, wherein the substrate with the embedded sensor circuitry is either a printed circuit board (PCB) or a flexible circuit substrate and the wire loop is directly wire bonded to the PCB or the flexible circuit substrate. 24. A method of manufacturing a fluid flow sensor, comprising the steps of: (a) providing a substrate;(b) providing at least one pre-formed wire; and(c) attaching the pre-formed wire to the substrate using a non-monolithic forming process, wherein the pre-formed wire is attached as a wire loop that acts as a sensor element. 25. The method of claim 24, wherein step (c) further comprises wire bonding the pre-formed wire to the substrate via a wire bonding process. 26. The method of claim 24, wherein step (c) further comprises micro-welding the pre-formed wire to the substrate via a micro-welding process.