One of the things that will always remain intriguing to many is the creativity and innovation behind touch sensor applications. For a long time, implementing such designs has remained to be a complex venture demanding the use of several components leading to expensive products. However, all this is bound to change following the introduction of a highly integrated capacitance-to-digital converter IC by ON Semiconductor.
The premier high performance silicon solutions provider has come up with the LC17A00AR, which is first in a series of ON (News - Alert) Semiconductor sensor integrated circuits. The solution renders the complexity of replacing mechanical switches with capacitative sensors obsolete leading to the production of simpler appliance control units interfaces without compromising on service quality.
LC717A00AR features eight capacitor sensor units and eight digital outputs. These are linked by a proprietary differential capacitance detection technology that ensures peak sensitivity whilst maintaining high noise resistance.
The switch is the simplest element in all this agglomeration of technology. It feeds a logic circuit that does the actual detection of the ON/OFF states and outputs the results without having to call for the services of control software or additional resources.
Why this obsession in sensitivity and noise resilience while there already are some very awesome touch-controlled gadgets in the market? The answer lies in the targeted location of use. While sensitivity might not be an issue for gadgets whose control panel does not need any protective cover, it is a real worry for those needing a protective air gap or a thick glass cover. Such include washing machines, refrigerators and cooking appliances.
Apart from the heightened sensitivity, the anti-noise control system allows the device to compensate for variations in temperature and humidity, thus preventing false touch detection and or operational failure.
The 2.6 - 5.5 volts compatible device can operate as a standalone unit. In this mode, it can allow parameter modifications through signals sent from an external microcontroller accessible through an integrated serial interface configurable to I2C or SPI operation. On average, the LC717A00AR consumes 320 micro-amps at a supply voltage of 2.8 volts and has a rated operational temperature range of between -40oC - 105oC.
Edited by Brooke Neuman