Semtech has rolled out easy-to-use capacitive sensing IC that can be used in television applications that require energy efficient touch button operations. The SX8660/61 is an eight channel touch sensor that is driven by integrated LEDs and has an extended 10cm proximity sensing range.
The new sensor is compatible with many types of televisions as it contains an analog output interface (AOI) that can replace many button operated remote controllers.
The analog-to-digital converter on the IC is extremely sensitive to touch even through thick cover material (upto 5mm). This sensor is energy efficient and consumes very low current (70µA) for its operation and hence satisfies all the eco-regulations for televisions. They come in packages of sizes as small as 4mm x 4mm 28-QFN and can operate over a wider temperature range of -40°C to +85°C.
Eight, 256 step LED drivers are present on the sensor platform, which come with individual intensity fading control that is suitable for human vision. The touch buttons fade on when touched and off when released and the interval speed and the fade off light intensity are to be set by the designer. The marketability of the sensor is increased by the multi-time programmable firmware that can be tailor- made by altering parameters like scan time, slave address, channel gain and sensitivity thresholds to suit the application. Need for external resistors and capacitors is absent as capacitive sense inputs are already present.
Sam Massih, the Director of Consumer Analog products for Semtech, says that the SX8660/61 scores over the competitors by having the touch sensing and proximity sensing integrated in one unit and there is no need for external components. He further added that as a result of this integrated unit the design is greatly simplified and the cost of material also comes down.
The SX8661 comes with a pre-configured quick start mode and seven buttons, one AOI and seven LED drivers with PWM fading features. On the other hand, the SX8660 comes with a quick-start mode with eight buttons, two AOI’s, one buzzer output and only five LED drivers with PWM fading. Both these devices are equipped with a smart automatic offset compensation function, which makes them fool-proof against false triggers due to temperature, humidity and dust.
Source: http://www.semtech.com