sx8638 Semtech Corporation, sx8638 Datasheet - Page 24

• Manufacturer Part Number: sx8638
• Description: Low Power, Capacitive Button And Slider Touch Controller 8 Sensors With Enhanced Led Drivers And Proximity
• Manufacturer: Semtech Corporation

ADVANCED COMMUNICATIONS & SENSING
3.15 Interrupt
3.15.1 Power up
During power up the INTB is kept low. Once the power up sequence is terminated the INTB is released
autonomously. The SX8638 is then ready for operation.
During the power on period the SX8638 stabilizes the internal regulators, RC clocks and the firmware initializes all
registers.
During the power up the SX8638 is not accessible and I2C communications are forbidden.
As soon as the INTB rises the SX8638 will be ready for I2C communication.
3.15.2 Assertion
INTB is updated in Active or Doze mode once every scan period.
The INTB will be asserted: at the following events:
3.15.3 Clearing
INTB is updated in Active or Doze mode once every scan period.
The clearing of the INTB is done as soon as the host performs a read to the IrqSrc I2C register or reset is
completed
Revision 7_6, September 10
• if a Button event occurred (touch or release if enabled). I2C registers CapStatMsb and CapStatLsb show the
• if a Slider event occurred (touch, release, move high, move low or position change). I2C registers
• if a GPI edge occurred (rising or falling if enabled). I2C register GpiStat shows the detailed status of the GPI
• when actually entering Active or Doze mode either through automatic wakeup or via host request (may be
• once compensation procedure is completed either through automatic trigger or via host request (may be
• once SPM write is effective (may be delayed by 1 scan period),
• once NVM burn procedure is completed (may be delayed by 1 scan period),
• during reset (power up, hardware RESETB, software reset).
detailed status of the Buttons,
CapStatMsb, SldPosMsb and SldPosLsb show the detailed status of the Slider,
pins,
delayed by 1 scan period). I2C register CompOpmode shows the current operation mode,
delayed by 1 scan period),
Figure 24
© 2010 Semtech Corp.
Low Power, Capacitive Button and Slider Touch Controller
(8 sensors) with Enhanced LED Drivers and Proximity
Power Up vs. INTB
24
DATASHEET
www.semtech.com
SX8638