STMPE2403 datasheet(22/63 Pages) STMICROELECTRONICS

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System controller

STMPE2403

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7.5

Autosleep

Host system may configure the STMPE2403 to go into sleep mode automatically whenever

there is a period of inactivity following a complete I2C transaction with the STMPE2403.

This inactivity means there is no intended I2C transaction for the device. For example, if

there is I2C transaction sent by the host to other slave devices, the STMPE2403 device will

still be counting down for the auto-sleep. The STMPE2403 device resets the autosleep

time-out counter only when it receives an I2C transaction meant for the device itself. This

autosleep feature is controlled by the System Control Register 2.

All events that trigger an interrupt (KPC, Rotator controller, Hot-Key) would result in a

transition from SLEEP state to OPERATIONAL state automatically. The wake up can also

be performed through I2C transaction intended for the device.

7.6

Keypress detect in the hibernate mode

When in hibernate mode, a keypress detect will cause the system to go into sleep mode.

The sleep clock (32KHz) will then be used to debounce the key to detect a valid key. If the

keypress is detected to be valid, the system staty in the sleep mode. If the key is detected to

be invalid, the system will go back into hibernate mode.

STMPE2403 データシート(PDF) 22 Page - STMicroelectronics