FUSB308BVMPX datasheet(16/53 Pages) ONSEMI

16 / 53 page

FUSB308B

www.onsemi.com

Discharge during a Connection

The discharge functions can be manually activated via the

PWRCTRL.FORCE_DISCH register. The discharge

pull−down is specified by RFULL_DISCH. The FUSB308B

will automatically disable discharge when VBUS reaches

VBUS_STOP_DISC threshold.

Figure 14. Source Discharge During a Connection

PWRCTRL.FORCE_DISCH

Apply RFORCE

VBUS_STOP_DISC

time

VBUS

tSrcSettle

vSrcNew

Watchdog Timer

The watchdog timer functionality is enabled whenever

TCPC_CTRL.EN_WATCHDOG is set to 1b. The watchdog

timer should only be enabled after an attach when the device

Attached.Src,

Attached.Snk

Apply.ROLECONTROL states. The watchdog timer starts

when any of the interrupts that are not masked in the Alert

watchdog timer is cleared on an I2C access by the TCPM

(either read or write). If the INTB pin is still asserted after

this I2C access, the watchdog timer will reinitialize and start

monitoring again until all of the Alerts are cleared or until

the INTB pin is de−asserted.

When the watchdog timer expires, the FUSB308B will

immediately disconnect the CC terminations by setting

ROLE_CONTROL bits 3..0 to 1111b, disable all

SRC/SRC_HV or SNK outputs, discharge VBUS to

vSafe0V, and set FAULT_STATUS.I2CInterfaceError.

FUSB308BVMPX Datasheet(PDF) 16 Page - ON Semiconductor