Question: What is the valid operating voltage range for the CY8CMBR3xxx family of CapSense Express devices?
CY8CMBR3xxx CapSense Express devices are designed to operate at one of two voltage ranges: 1.8 V ±5% or 1.8 to 5.5 V.
CY8CMBR3xxx CapSense Express devices are not designed to operate continuously over the full range of 1.71 V to 5.5 V, but can operate continuously over the full range of 1.8 V to 5.5 V. This is important to know if your application is battery-powered and the operating voltage may gradually decrease as the battery gradually discharges.
Depending upon the operating voltage, you must enter the appropriate value for the SUPPLY_LOW_POWER bit in the I2C register map for the best CapSense performance. Note that setting an incorrect value for the SUPPLY_LOW_POWER bit in the register will not damage the part. However, the CapSense performance may be affected.
When operating in the 1.8 to 5.5 V range, the VCC pin must be connected to a 0.1μF capacitor and must not be connected to any other power source. When operating in the 1.8 V±5% range, VCC and VDD pins must be connected together.