CAPSENSE™ & MagSense Forum Discussions

Hello

I am working on a project in which I am using this IC "cy8cmbr3108-lqxit",  for the touch sensing.

I am facing issue with the touch sensing.

I am using EZ-Click for making the device configurations and using the API's provided by the Cypress for programming the Touch IC, but still device is not sensing the touch.

When I check with DSO in the Touch Pins I am seeing some voltage of 240 mV and not seeing any pulse which is configured at 60ms rate.

I had checked the communication and it is working fine but I am not able to debug the issue.

If someone can help, that will be great.

Added Schematic for the reference and I am using stm32 for controlling the touch IC.

Regards

Vaibhav Bansal

Do you have a solution for sensing distance in the range of 0-10 cms with a precision of +- 1 mm, but able to work in a plasma cutting machine?   

The porpouse is to compensate sheet deflections due to the heat that plasma generates (near 400 Celsius) on the surface being cutted, but in a very noisy electromagnetic environment, as the plasma flame is an electric arc modified with a high pressure air flow. 

I've tryed with inductor sensors and they fail when cutting thick metal sheets.  I suppose that capacitive fails too.  I've not tryed with ultrasonic, but it is possible that the plasma generate too some noise of this kind. 

So, if you have a probed solution on this, I'll be happy to know about it.

Luis

Hi, i have a few thousand boards to produce for an outdoor keypad exposed to rain under 7mm of glass. We used to use CY8CMBR3116-LQXI but it seems like it is either out of stock or incredibly expensive.

Is there an alternative that does the same job (low power 16 keys, rain OK) that is available and worth trying?

thanks in advance!

Greg

We've been using the CY8C20237-24LKXI in a capsense application where we need water rejection with capsense not being blocked. The PSOC1 above has a shield electrode which makes this possible. This part however is not available anymore on short notice and we need to produce 30.000 boards.

What would be the best alternative for the CY8C20237 that will be available on short notice? I was looking at the PSOC4 range, but I can't find any parts available.

Hi all,

I have a 2-layer PCB using a Capsense CSX touchpad, following the capsense design guidelines as much as possible

The touchpad is in the blue circle, and as you can see no circuitry at all is under it, as advised in the documentation.

Now, I have a space critical application where I would need the PCB to be the size of the touchpad, so I need all of the circuitry behind it.

1. Is it possible to do so without introducing too much noise in the sensors?

2. Of course, I would use a 4-layer PCB. What would be the ideal layer stack to minimize noise. Maybe a hatched ground in one of the internal layers?

Thanks a lot! have a nice day.

Hello,

I have a question related to the proximity consumption.  I noticed that the proximity consumption is similar to scan 12 buttons at 200 ms.  Is it possible to find a spec somewhere describing proximity current?

My board with 1 button scan only, I measured ~40 uA.

Board with 12 buttons, no proximity enabled : ~110 uA.

Board with 12 buttons, proximity CS1 activated : ~105 uA.

So, I'd preferred to have consumption with around 40uA like one button.  It's why I am confused about this... bad configuration?

Thanks

Hi: I am using CY8CMBR3108 and, because the touch sensors become too sensitive after some time, I periodically send a RESET (CNTRL_CMD with 0xFF) command to it. However, for some reason (ESD?) I already had the situation that one (twice) or all (3 times) sensors of my product stopped working. The automatic RESET doesn't recover it. Only if I turn off the power and restart the unit, the sensors are back and all works.

After power-up I send the configuration that you see below in this post.

I find it very strange that, if after RESET (without power-off) I repeat the same configuration sequence (that is always performed after power-up), then no sensor is working. It is strange that the IC only accepts the configuration once after power-up!!!

The Power-up sequence is:

WriteToCs(SENSOR_EN, 0x001B, 2);
WriteToCs(FSS_EN, 0x0000, 2); 
WriteToCs(GPO_OUTPUT_STATE, 0x1B, 1); 
WriteToCs(BASE_THRESHOLD0, 200, 1);
WriteToCs(BASE_THRESHOLD1, 200, 1);
WriteToCs(FINGER_THRESHOLD2, 200, 1);
WriteToCs(FINGER_THRESHOLD4, 200, 1);
WriteToCs(DEVICE_CFG0, 0x00, 1);
WriteToCs(DEVICE_CFG2, 0x14, 1); 
WriteToCs(SENSITIVITY0, 0xCF, 1);
WriteToCs(SENSITIVITY1, 0x03, 1);
WriteToCs(REFRESH_CTRL, 1, 1);
WriteToCs(CTRL_CMD, 3, 1);
nack = 1;
Delay(C100_MS);
while (nack)
{
nack = CsdRead(CALC_CRC,buff,2);
Noop();
}
val = buff[1];
val <<= 8;
val += buff[0];
WriteToCs(CONFIG_CRC, val, 2);
WriteToCs(CTRL_CMD, 2, 1);
Delay(C100_MS);
nack = CsdRead(CTRL_CMD_STATUS, buff, 1);

Can somebody help?

Hi,

I'm currently using "CY8CMBR3108" in a project. But for mass production we can't find this component in stok. So I found "CY8CMBR3145" PN component but I can't find any docs for it.

Could you please help me about the situation?

I have 2 CY8CMBR3116-LQXI on the same I2C bus. Using the reset pin, I was able to program them with individual I2C addresses and had my unit working really well.

One day, something happened that caused the chips to loose the configuration which caused the I2C addresses to go back to 0x37.

What could cause the configuration to be lost?

How can I prevent it?

Is there a way to lock the configuration?