CY3280-MBR Cypress Semiconductor Corp, CY3280-MBR Datasheet - Page 30

• Manufacturer Part Number: CY3280-MBR
• Description: BOARD EVAL CAPSENSE EXPRESS
• Manufacturer: Cypress Semiconductor Corp
• Series: CapSense® Express™ SmartSense™r

Specifications of CY3280-MBR

• Design Resources: CY3280-MBR Schematic CY3280-MBR Bill of Materials CY3280-MBR Gerber Files CY3280-MBR Board Layout
• Sensor Type: Touch, Capacitive
• Sensing Range: 4 Buttons/Keys
• Voltage - Supply: 3V
• Embedded: No
• Utilized Ic / Part: CY8CMBR2044
• Operating Voltage: 1.71 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Current: 2.88 A
• Silicon Core Number: CY8CMBR2044
• Silicon Family Name: PSoC
• Kit Contents: 2x AAA Batteries, Axial Capacitors 10pF, 22pF, 33pF, 68pF, Quick Start Guide
• Rohs Compliant: Yes
• For Use With/related Products: CY8CMBR2044
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Interface: -
• Sensitivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 428-3083

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Frequently Asked Questions
This section provides solutions for errors that you may encounter when working with the CY3280-
MBR kit.
Q. Power LED does not turn when power button is pressed
A. This can be due to the following reasons:
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Q. BTN1 and BTN2 does not work with 5 mm overlays
A. For a button sensor to work with overlay of specific thickness, the button should have the required
diameter. The diameter of BTN1 and BTN2 is not enough to support the 5 mm overlay. This also
means that to support particular overlay thinness, correct value of button diameter should be
selected in your design. To find the required button diameter for particular overlay thinness, refer the
CY8CMBR2044 data
CY8CMBR2044, and the
Q. Some buttons are too sensitive with 2 mm overlay
A. For a button to successfully work at correct sensitivity with given overlay, it is recommended to
choose the button size according to the design box. If design box recommendation is not followed,
buttons of bigger size may be oversensitive with thinner overlays.
Q. Touching on the bottom layer of PCB creates false trigger of buttons
A. Traces connecting CapSense sensor and CapSense controller are routed on the bottom layer of
the PCB. When those trace are touched, the sensors can create a false trigger. This is because, the
traces are touched without any overlay, making the trace very sensitive. However, in the actual
product, PCB and traces will not be accessible for the user and hence this is not a problem.
Q. When external capacitors are added to J5 to increase the parasitic capacitance of BTN2,
sensors produces false trigger
A. The BTN1 and BTN2 sensor are connected to J5 connector. When connecting the capacitor to the
sensor, sensor capacitance is increased. This is similar to the capacitance increase due to the finger
touch. Therefore, the CapSense controller misinterprets it as finger touch. When external capacitors
are connected, the power should be toggled to offset the capacitance increase.
Q. After changing the switch positions, no change is observed in kit operation
A. Hardware strapping inputs are read by the CapSense controller only during the boot up.
Whenever a hardware strapping input status is changed, CapSense controller should be rest using
XRES pin or power should be toggled for the change to take effect.
The kit is not powered from any of the power sources. Ensure that there is a power supply.
The battery connected to the kit does not have charge. In this case, replace the old batteries with
a new AAA battery set or try powering the kit from external power source.
Battery inserted in reverse. Note that the polarity of the battery should match the polarity mark
given on the kit. Follow the steps in section
correctly into the battery holder.
CY3280-MBR CapSense Express with SmartSense Auto-Tuning Kit Guide, Doc. # 001-64772 Rev. **
sheet, the application note,
Design Guide
Tool.
2.5 Power the Kit on page 11
AN59004 - Four Button CapSense Design using
to insert the batteries