The AMS smart capacitive sensing front end optimizes speed, resolution and power

     Ams introduces the PCap04, a configurable capacitive sensing front end that enables sensor manufacturers to balance speed and resolution to match their design needs. When optimized for speed, the PCap04 can capture sensor measurements up to 50,000 times per second and digitize them. When the sampling speed is slow to optimize accuracy, the PCap04 can achieve a measurement resolution of 8aF.

     The configurability of the device also allows sensor manufacturers to achieve a good trade-off between measurement speed and power consumption. In low power mode, the PCap04 requires only a low current of 4.0μA. Ams has developed a demonstration board without an external power source, in which the PCap04 relies on energy harvested from the RF field generated by NFC readers such as mobile phones fine.

     PCap04IC is suitable for any sensing element where capacitance changes. The device has 6 capacitance measurement channels, making it ideal for use with other sensing elements, such as measurement

     Measure pressure, force, position, tilt, humidity, weight, level and other sensing parameters. The output of the PCap04 can display the original measured capacitance value in PWM or PDM. The device also has a DSP to help process the sensor measurements and convert them to digital values via an I2C or SPI interface. It can handle a wide range of input capacitance values, from as low as 1pF to as high as 100nF.

     The PCap04 offers a variety of built-in configurable options, including support for ground, floating, differential, and differential ground sensor connections. The DSP can run AMS open source code and user generated code to implement functions such as measurement value linearization and conversion. Ams provides evaluation kits and easy-to-master software development tools for design engineers to develop, test, and debug code running on PCap04.

     JoseVinau, Director of Medical and Special Sensor Marketing at AMS, said: "The PCap04 provides sensor manufacturers with a flexible alternative to other sensor front ends with fixed operating characteristics in the market today. The unique advantages offered by this device enable sensor manufacturers to adapt the operation of the sensor front end to meet the needs of their specific applications.