Hi,
Our customer is planning on a new IoT device project, battery operated and wants to use capsense to (touch) wake up and also using capsense for device functions control (exact functions via capsense not fully defined yet).

Our customer wants to know first if IFX has feasible capsense solution as the material of their IoT device is quite special !
The base material of the device will be silicone, and our customer will also have a detachable sleeve/jacket on the device which is made of cotton or fleece type of material.  The base silicone material will have a thickness up to 4mm.   The cotton/fleece sleeve jacket will also have a thickness up to 4mm.  Altogether up to 8mm (under 1cm).

Our customer is asking if any PSoC4 with Capsense can support/operate on both :
a). just on the base silicon material (up to 4mm thickness)
b). on top of the base silicon material + the cotton/fleece type of material (overall up to 8mm thickness)

Can the PSoC 4100S Max and/or the new PSoC 4000T (fifth-generation CAPSENSE™ and MULTI-SENSEtechnology) meet the customer's requirements ?
If yes, please help to advise which specific PSoC4 part # and please also help to provide any relevant application note(s).

Much appreciated !

Hi,

I made a two layer PCB using the CY8CMBR3116 touch controller. I followed all the design guidelines and in particular made the top layer hatched ground plane with 25% fill and the bottom layer hatched ground plane with 17% fill.

The board works, with one odd problem: when I place the PCB on a plastic surface (ABS) so that the bottom layer is against the plastic, then when I press one of the touch sensors, it registers many fake / ghost touches that aren't actually happening. It seems like the smallest bend in the PCB, pushing it closer to the plastic, causes these incorrect button presses to be registered.

When I put some thin packaging foam between the PCB and the plastic, then the problem goes away and the sensors are very accurate.

So I created two new versions of the PCB, with 45% and 65% hatched ground plane fill on the bottom layer - but the problem still happens.

Does anyone know why this could be happening? Could any EZ-Click firmware settings help fix this? Any help appreciated, thanks.

Hello,

I use capacitive touch buttons with the CY8CMBR3116-LQXI components.

The datasheet recommends parasitic capacitances (Cp) between 5 pF and 45 pF for buttons.

I measure, with the EZ-Click 2.0 software, Cp between 2 pF and 4 pF. Is a Cp value below 5 pF a problem?

For information, I use buttons with a diameter of 9 mm and trace lengths less than 40 mm. The width of the traces is 7 mil (0.17 mm). Button-ground clearance is 2mm (because the glass thickness is 5mm). A hatched pattern is at the top and bottom (2-layer PCB) and it is connected to the SH pin.

Thank you.

Rob

Hi,

We have a PCB using the CY8CMBR3116 touch controller. One thing we noticed is when the customer is pressing a button on power up, the button will not work. We think this is because the IC is calibrating the sensitivity on startup, and it detects the presence of the finger and assumes it is part of the environment, and so increases the threshold.

Is there any way to prevent this? Otherwise, we need to include instructions to our customers to not touch the sensors when powering up the unit...

Also, is it possible to detect a touch is pressed on power up using the registers, and force calibration only after it is removed, using software?

Any help appreciated, thank you.

Hello Guys,

This is İsmet, Im new for cypress, im looking for how can i control this cy8cmbre3110 or 3102 with stm32L431, i found a code with arduino wire.h library can control it with i2c protcol but i have no idea about how to control stm32 with my cy8cmbr3110 or 3102 capsense?

 waiting your kind replies!

 #capsens #cy8cmbr3110 #stm32 #arduino CY8CMBR3102-SX1IT