CAPSENSE™ & MagSense Forum Discussions

I have a PSOC 4100S Plus on a custom board and am running a sensing circuit with an active shield and the shield tank capacitor enabled.  When looking more closely at the startup and pre-charging I noticed that the tank capacitor lags the mod capacitor and sensor electrode when pre-charging (even though my understanding is they are all connected to the same bus).  Due to this lag, and slower charge rate during sampling, there exists a potential between the shield and sensor traces which I believe is impacting our measurement.  I have looked through the documentation and technical reference, but the isn't much explicit information on how the pre-charging works and how the internal switch network is configured.  Is there any additional details on how this functions or insight as to why the shield tank is lagging.  The problem doesn't appear to exist if the tank capacitor is disabled.

Yellow is sensing pad, Blue is shield tank capacitor.

 Thanks

Dear Sir/Madam,

I am on beginner level on PSoC® Development and Programming. I am searching a suitable development kit which can help me to learn and use later on in my application. Is it possible to use CY8CKIT-001 PSoC® Development Kit for haptic application (HMI) or any other suggestion?

Thank  you in advance

Best regards,

Chauhan

Hi,

We are working on a design with the CapSense CY8CMBR3108. We are experiencing issues communicating with this device from our iMX application processor. We have found the following:

If we try and read from the device a single time, it usually fails. Occasionally (~25%) it will return the correct value.

If we quickly send a read command with less than 200ms delay, the second read always (100%) works and returns as expected.

If we increase the delay between reads to 4sec, we go back to failures most of the time. 

We've tried changing the speed of teh I2C bus from the host, but this make no difference.

I suspect there may be a timing issue? Maybe the device is going to a lower power state and repsonds slower? However, the STATE_TIMEOUT = 10. We tried setting it to 0 with no change.

Any ideas why we get intermittent read results on our fist attempt but always works on the second try?

Thanks,

James

Hello,

I have a design with capacitive buttons on a FPC (Flexible Printed Circuit) that connects to a PCB with a CY8CMBR3108 controller. The Application Note at https://www.cypress.com/file/46366/download does not have a good example on how to construct the shield electrode on a FPC.

Section 4.4.4 best describes what I intend to design but the section does not show a shield electrode. In this section, #1 states that the hatch fill for the shield signal should only be in the top layer. However, #2 states to place a ground trace in parallel to the sensor trace in the FPC connector. My question is: do I need a ground fill in the FPC if I am using a shield signal? If so, where do I put the ground fill?

Thank you

Hi all,

simple question, I could not find the info in the datasheet/design guideline for capsense 4 and 6. Are the CSX and CSD methods driving the sensor electrodes with AC or DC current?

I know CSX is probably AC as it checks for variations of current through Cm.

Thank you!

I am trying to locate Cypress documentation for low-level PSoC 62 CapSense registers and how to use them.
I have found  mid-level and high-level documentation.

I have created a working design based on the CY8CPROTO_062_4343W and the CapSense library.

My design does not fit in with the available CapSense sensor types but it does use the CapSense sensing hardware.

Currently I am using the CapSense library to collect the touch data for one of the standard CapSense sensor types, but I am having to modify the behaviour within the pre and post interrupt calls to fit in with the new design.

I do appreciate how much work has gone into the CapSense library and how it is protecting me from the low-level details and chip variations.

How can I recreating a finger touch for an automatic darution test of the CapSense Button of the Endproduct. (e.g. a metal plate or an resistor switch to GND?

Hi,

As suggested by Hari, I have reached till point of, getting CRC code for required changes made through EZ click , so I generated my CRC code, it is 0xa3f7 in my case .

My query here is I am unable to proceed with further steps i.e. point no. 2 and 3 from page 70.

Can you share your thought on this how can I program this. I tried different methods but CTRL_CMD  and CTRL_CMD_ERR both has 255 as data in them.

Thank you.

Regards,

Nikhil S.

请问CY8CTMA461AS-33 ，哪种编程器（烧录器）可以读写，数据在母片中!

こんにちは、

1.AN63846の2.9 耐液性の回路で質問があります。
図2-32の回路で質問です。

GUARDは、新たにCSを追加して、それをGUARDに割り当てるということでしょうか？
SH はシールドグラウンドということでよろしいでですか？
この時のGUARDは、CYSHのCAPSENSのBASIC部でBUTTONで割り当てればよいですか？

また、 耐液性のsampleコードがありましたらお教えください。

以上

よろしくお願いいたします。