In a meeting last week with a vendor releasing an inductive touch sensor (sort of), I got excited by the number of possibilities that were offered by a device like this one. The device Im referring to is actually an inductance-to-digital converter (LDC), a part that uses coils and springs as inductive sensors to deliver higher resolution, increased reliability, and more flexibility than existing sensing solutions. And this comes at a lower cost, too.
This contactless sensing technology can be used to measure the position, motion, or composition of a metal or conductive target, as well as detect the compression, extension, or twist of a spring. Developed by Texas Instruments, the first device in the family is dubbed the LDC1000.
Applications for inductive sensing range from simple push buttons, knobs, and on/off switches to high-resolution heart rate monitors, turbine flow meters, and high-speed motor/gear controllers. Given their versatility, LDCs can be used in many different markets, including automotive, white goods, consumer electronics, mobile devices, computing, industrial, and medical.
Specifically, the LDC1000 offers a level of resolution that enables sub-micron resolution in position-sensing applications with 16-bit resonance impedance and 24-bit inductance values. And because its contactless, its immune to nonconductive contaminants, such as oil, dirt, and dust, which can shorten equipment life. The part consumes less than 8.5 mW during standard operation and less than 1.25 mW in standby mode.
An evaluation kit, the LDC100EVM, is available for $29. In small lots, the part costs $2.95. Click here for information about sensing in general and a video that explains the technology further.