Azoteq Announces Sensitivity Breakthrough in Capacitive Proximity Sensing

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Azoteq’s ProxSense® can sense down to 20 atto farads with a Signal-to-Noise ratio of 1000:1


Azoteq’s industry leading sensitivity and robustness open numerous applications such as intelligent user guidance even before physical contact is made in cost sensitive capacitive sensing applications

Azoteq, the world leader in capacitive proximity sensing, announced that their latest generation of proximity and touch controllers can sense capacitive changes as small as 20 atto farads. This sensitivity allows reliable proximity detection of over 300 mm or 12 inches on practical electrodes. One atto farad (1e-18 farads) is one million times smaller than one pico farad (1e-12 farads). Typical competitive devices can detect changes of 0.1 to 1 pico farad.

Azoteq combined these breakthrough levels of sensitivity, industry-leading (~1000:1) SNR and RF immunity into cost-effective capacitive controllers. These benefits relax the common design constraints normally imposed on designers, and the automatic tuning algorithm ensures that no calibration is required in manufacturing. This allows designers to use thick overlay materials of up to 50 mm or more, unusual overlay materials such as wood, and touch buttons in extremely small spaces. With ProxSense® a touch key is easily realized with mere edge plating on a PCB. Proximity detection is natively offered on all touch key controllers, opening up possibilities for more intuitive user interfaces. This includes such as wake-up from standby, pre-emptive menu selection and automatic backlight illumination.

ProxSense® was developed and patented from the ground up using novel analog design techniques for ultra sensitive capacitive measurements. The result is a proximity and touch controller that can sense changes of 20 atto farads in projected capacitance mode and 200 atto farads in self capacitance mode. In contrast to common perception, Azoteq has proven that long range can reliably be achieved with projected capacitance. R&D in novel micro-electronic designs allows for this groundbreaking sensitivity whilst maintaining industry-leading ESD immunity and low current consumption.

“Azoteq’s industry-leading sensitivity and robustness open numerous applications, such as intelligent user guidance, even before physical contact is made in cost-sensitive capacitive sensing applications” said Frederick Bruwer, CEO of Azoteq. “ProxSense® is also ideal for battery applications, since consumption is less than 10 microamperes while sensing proximity,” he added.

Azoteq will be releasing a next generation family of controllers based on the ProxSense® technology during the first and second quarters of 2012.


  •     2, 3, 9 and 12 channels
  •     Self- and projected capacitance modes
  •     Proximity and touch on each channel
  •     Distributed proximity channel formed by multiple keys
  •     On-chip hardware compensation for sensitivity-reducing objects
  •     I2C interface
  •     Automatic tuning to optimum sensitivity
  •     Supply voltage of 1.8V to 3.6V
  •     Multiple low-power modes
  •     Internal voltage regulator and reference capacitor
  •     Large proximity-detection range
  •     Automatic drift compensation
  •     Industrial temperature range
  •     MSOP-10 and QFN(3x3)-16 packages


  •     Consumer electronics: televisions, Blu-Ray players, set-top boxes
  •     Computers and tablets
  •     White goods and appliances
  •     Office equipment, toys, sanitary ware
  •     Proximity detection that enables activation of backlighting
  •     Wake-up from standby applications
  •     Replacement for electromechanical switches
  •     GUI trigger and GUI control proximity detection

About Azoteq
Azoteq (Pty) Ltd ( is the world leader in capacitive proximity solutions. An extensive portfolio of controllers is offered for touch keys, sliders, scroll wheels and touch screens in consumer and industrial applications. Azoteq has design and manufacturing centers in South Africa and China. Azoteq has sales offices and distributors in South Africa, Asia, Europe and the USA.

Azoteq’s novel technology is protected by numerous patents, both issued and pending. A list of patents is available at

IQ Switch®, ProxSense®, LightSenseTM, AirButton®, DYCALTM and the IQ logo are trademarks of Azoteq (Pty) Ltd.

Editorial contact and interviews:
Kobus Marneweck


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Kobus Marneweck
Azoteq, Inc
+1 619 278 9011
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Kobus Marneweck
Azoteq, Inc
+1 619 278 9011
Email >
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