Cypress CapSense Express CY3280-MBR, Руководство пользователя

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CY3280-MBR CapSense Express with SmartSense Auto-Tuning Kit Guide, Doc. # 001-64772 Rev. ** 9
Kit Operation
The kit can be powered from three sources. This includes power from on-board battery and external
power through the J2 connector. A protection circuit is provided to prevent damage if both these
sources are connected at the same time. The protection circuit allows only one power supply to be
active at a time. The supply that has higher potential powers the kit. Therefore, to power the kit with
less than 3 V external power, the battery should be removed. To power the kit from the battery,
external power supply should not be connected or should not be higher than the battery voltage
(3 V).
The two power sources mentioned above are connected to a series pass switch, which is controlled
by the CapSense based power button. An LED is used to indicate the power ON condition of the kit.
The third power source option is through the J5 connector; this power supply does not have
protection circuit. It is recommended not to power the kit from any other source when the external
power through J5 is connected.
Four CapSense buttons and receptive LEDs are connected to the CapSense controller used for
demonstration. The output signals and hardware strapping inputs are also connected to J1 and J2
connectors. This helps to connect them to host and monitor status and control the CapSense con-
troller.
2.3 Controller Pin Assignment Details
The following table shows the pin assignment of the CapSense controller. To learn how to assign
pins for your design and recommendations on pin selection, refer the
CY8CMBR2044 data sheet .
Pin Label Description Unused
1 GPO1 GPO activated by CS1 Leave open
2 GPO0 GPO activated by CS0 Leave open
3 Toggle/FSS Controls FSS and toggle features Ground
4 Delay Controls delay off time Ground
5 CS0 CapSense input 0 Ground
6 CS1 CapSense input 1 Ground
7
V
SS
Ground
8 CS2 CapSense input 2 Ground
9 ARST Controls auto reset delay Leave open
10 CS3 CapSense input 3 Ground
11 XRES Device reset, active high, with internal pull down Leave open
12 ScanRate/Sleep Controls scan rate and deep sleep Ground
13
V
DD
Power
14 GPO3 GPO activated by CS3 Leave open
15 CMOD
External integrating capacitor, connect a 2.2 nF
(±5%) between this pin and ground
16 GPO2 GPO activated by CS2 Leave open