Low-power Sensing for Capacitive Sensors
The combination of a capacitive sensor with a specific detection material entails certain requirements on the readout circuitry. Commercial off-the-shelf capacitive sensing circuits do not allow accounting for these special needs like low voltage and low current operation. The readout of single sensors can be achieved using discrete components, however, this approach leads to the design of a large circuit area with an elevated power consumption. This hinders extending the ASIC to a larger number of sensor channels, as it is the project goal.
The ASIC will convert the capacitive value into a digital representation within a few tens of microseconds, while it can switch into a power down mode in between. This approach, in combination with a low current sensing system, allows achieving an average power consumption of less than 20 µW for the readout of 8 channels.
Cost effective production of the ASIC in small volumes can be achieved by using EUROPRACTICE services.