SX8661Z datasheet(77/87 Pages) SEMTECH

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ADVANCED COMMUNICATIONS & SENSING

DATASHEET

Revision v4.0, February 2016

www.semtech.com

SX8661Z

Low Power, Capacitive Button Touch and Proximity Controller

(8 sensors) with LED Drivers and Analog Output

6.8

Monitor Mode

Monitor mode allows the host to read “real-time” sensor information (CAPxRaw, CAPxAvg, CAPxDiff).

It is enabled by setting bit 2 of I2C register SpmCfg (address 0x0D).

When enabled, it uses a specific monitor scan period (Cf below) and generates an interrupt every time a new full

set of data is available (hence every scan period).

Address Name

Bits

Description

0xF9

MonitorScanPeriod

7:0

Monitor Mode Scan Period

0x00: Reserved

0x01: 15ms

…

0x0D: 195ms (default)

…

0xFF: 255 x 15ms

Monitor mode scan period is located at address 0xF9 can be written similarly as SPM data (Cf. §6.6.1).

Interrupt is cleared normally by reading I2C register IrqSrc (address 0x00) but no specific flag is set.

CAPxRaw/Avg/Diff data can be read similarly as SPM data (Cf. §6.6.2).

Base address BA = 0xB4 is the beginning of the CAPxDiff data location and data are organized this way:

0xB4: CAP0Diff, MSB

0xB5: CAP0Diff, LSB

0xB6: CAP1Diff, MSB

etc...

Values are coded 16bits signed 2's complement format and updated at each scan period.

Base address BA = 0x80 is the beginning of the CAPxRaw data location.

Base address BA = 0x9A is the beginning of the CAPxAvg data location.

Data should be read before the next interrupt occurs (i.e. within one scan period).

SX8661Z Datasheet(PDF) 77 Page - Semtech Corporation