Does the pad on the underside of the AD7143 (QFN-like package) have to be grounded for the IC to work?
I have connected everything up except this pad, and the chip won't respond over I2C (no acknowledge bit).
Sorry for the delay in getting back to you. If you need multiple sensor inputs then have you considered maybe the AD7142 or AD7143 parts? These parts have multiple sensor inputs so they would reduce the need to use multiple AD7746 chips.
The AD7746 cannot be used for single electrode sensing; shorting the Excitation pins to the CIN pins will saturate the readings of the sensor.
The AD7747 is the only single ended device in this family, but you could look at the CapTouch…
Basically I want to oscillate my sensors so they only detect objects on only one of their sides, not both. Something as what is shown in this pdf in section 2.1 http://www.ti.com/lit/an/snoa926a/snoa926a.pdf
When I say "other capacitive converters…
there are couple of parts that provide more number of channels but they are limited to applications such as single electrode capacitance sensors or have touch sensor type of applications.
For a project, I want to differentially sense multiple capacitive channels (non-touch application), and I am thinking of using 6-7 units of the AD7143 chipset. I was wondering if anybody knew a good multiplexer to switch between these chips…
I am trying to figure out how to control my AD7150 eval board using an external microcontroller (Cypress PSOC 4 Pioneer dev. kit). Does anyone have a step-by-step solution to do this, preferably with application code in the C programming language…
I would like to use some capacitive buttons (up to 8) in a shower control system. The buttons will be inside the shower box. The customer, wet because under shower, has to touch the buttons to interact with the system. Clearly is an hard moisture…