Datasheet

ManualsBrandsCYPRESS SEMICONDUCTOR ManualsDev KitsPCB design board

CY8CMBR3002, CY8CMBR3102

CY8CMBR3106S, CY8CMBR3108

CY8CMBR3110, CY8CMBR3116 Datasheet

Document Number: 001-85330 Rev. *G Page 27 of 37

Response Time

Response time for button and proximity sensors is the minimum

amount of time for which the sensor must be active/inactive

(touched or proximity present), for the device to detect it as a

valid activation or deactivation event.

For the CY8CMBR3xxx device family, response time numbers

for different sensors can be estimated using the design toolbox.

The following response time numbers are provided in the

toolbox:

■ R

FBT

: This value represents the response time for first button

touch when the device is in the Look-for-Touch or

Look-for-Proximity operational states.

■ R

CBT

: This value represents the response time for consecutive

button touches when the device is in the Active operational

state.

■ R

FST

: This value represents the response time for the first slider

touch when the device is in the Look-for-touch operational

state.

■ R

CST

: This value represents the response time for consecutive

slider touches when the device is in the Active operational state.

■ R

BSR

: This value represents the response time for button and

slider release events when the device is in the Active opera-

tional state.

■ RProx: This value represents the response time for detecting

valid proximity events on a proximity sensor.

■ RProx_release: This value represents the response time for

proximity release events on a proximity sensor.

CY8CMBR3xxx Resets

The CY8CMBR3xxx family of CapSense controllers has three

reset options – two hardware resets and one software reset.

■ Hardware Resets

❐ Power reset –Toggling the power on the V

pin of the

CapSense controller resets the controller.

❐ XRES reset – Pull the device XRES pin LOW for T

XRES

du-

ration and then pull it HIGH.

■ Software Reset

To reset the software, write one SW_RESET command to the

command register. All three resets are functionally equivalent,

and the CapSense controllers enter the Boot state (refer to the

Power Consumption and Operational States section) after any

reset.

Host Communication Protocol

The CY8CMBR3xxx CapSense controllers communicate to the

host through the I

C interface. I

C is a simple two-wire

synchronous communication protocol that uses the following two

lines:

■ Serial Clock (SCL) –This line is used to synchronize the slave

with the master.

■ Serial Data (SDA) – This line is used to send data between the

master and the slave.

The CY8CMBR3xxx I

C interface has the following features:

■ Bit rate of 400 kbps

■ Configurable I

C slave address (7-bit)

■ No bus-stalling or clock-stretching during transactions

■ Register-based access to the I

C master for reads and writes

■ Repeated START support

The CY8CMBR3xxx CapSense controllers can be part of a

single-slave or a multi-slave environment.

Figure 17. I

C Communication Between One Master

and One Slave

C Slave Address

To identify each device on the I

C bus, a unique 7-bit I

C slave

address is used. When the master wants to communicate with a

slave on the bus, it sends a START condition followed by the

appropriate I

C address. The START condition alerts all slaves

on the bus when a new transaction starts. The slave with the

specified I

C address acknowledges the master. All the other

slaves ignore further traffic on the bus until the next START

condition is detected.

HOST CY8CMBR3xxx

SCL

SDA