Quantum Research adds IP licensing option for patented charge-transfer sensing ICs

Southampton, UK: Quantum Research Group, the charge-transfer (QT) capacitive touch company, announces the QT1102, a ten-channel QTouch sensor chip. With this single device designers can create a scroller, for example a touch slider or wheel, together with six additional independent key channels. Each channel can be tuned for individual sensitivity simply by changing an external capacitor. Sensing is achieved by projecting sense fields through any dielectric such as glass or plastic. Near-proximity or touch is detected when the field is disturbed by a finger. Applications include control panels, domestic appliances, gaming devices and remote controls. The technology provides a cost-effective, robust and reliable alternative to electromechanical controls and switches.

The segmented scroller detects relative position and is formed by arranging a series of keys in a line, circle or some other shape. These are connected to four of the sensor channels in a repeating sequence. The device then processes the four sense measurements to provide information on the movement of a touch along the scroller, at the same time indicating whether the scroller is being touched. The chip detects relative movement rather than absolute position. The QT1102 can be synchronized with other similar parts or, simultaneously, to an external source to suppress interference.

Quantum’s patented adjacent key suppression (AKS™) suppresses touch from weaker signals and allows only the dominant key to be detected. This is particularly important where small control panels are used and a finger may cover more than one key. The scroller uses a special form of AKS to process the segments as a group relative to the other six individual keys.
Proven charge-transfer technology, used in spread-spectrum burst mode, ensures reliable operation and effective noise rejection.

The QT1102 operates from a single 2.7V to 5.5V supply, with less than 40µA typical current consumption at 3V in low power mode. It communicates via an SPI 5-wire interface, delivers fully de-bounced results and is housed in a lead-free 32-QFN package.

The device is available now priced at US$0.97 each for 100k quantities.