SWCS046I
– MARCH 2010 – REVISED JULY 2011
When the thermal shutdown temperature theshold is reached, the TPS65910 device is set under reset and a
transition to OFF state is initiated. Then the power-on enable conditions of the device is not considered until the
die temperature has decreased below the hot-die threshold. An hysteresis is applied to the hot-die and shutdown
threshold, when detecting a falling edge of temperature, and both detection are debounced to avoid any parasitic
detection. The TPS65910 device allows programming of four hot-die temperature thresholds to increase the
flexibility of the system.
By default, the thermal protection is enabled in ACTIVE state, but can be disabled through programming register
THERM_REG.
The
thermal
protection
can
be
enabled
in
SLEEP
state
programming
register
SLEEP_KEEP_RES_ON. The thermal protection is automatically enabled during an OFF-to-ACTIVE state
transition and is kept enabled in OFF state after a switch-off sequence caused by a thermal shutdown event.
Transition to OFF state sequence caused by a thermal shutdown event is highlighted in the INT_STS_REG
status register. Recovery from this OFF state is initiated (switch-on sequence) when the die temperature falls
below the hot-die temperature threshold.
Hot-die and thermal shutdown temperature threshold detections state can be monitored or masked by reading or
programming the THERM_REG register. Hot-die interrupt can be masked by programming the INT_MSK_REG
register.
INTERRUPTS
Table 13. Interrupt Sources
Interrupt
Description
RTC_ALARM_IT
RTC alarm event: Occurs at programmed determinate date and time
(running in ACTIVE, OFF, and SLEEP state, default inactive)
RTC periodic event: Occurs at programmed regular period of time (every second or minute)
RTC_PERIOD_IT
(running in ACTIVE, OFF, and SLEEP state, default inactive)
The embedded thermal monitoring module has detected a die temperature above the hot-die
HOT_DIE_IT
detection threshold (running in ACTIVE and SLEEP state)
Level sensitive interrupt.
PWRHOLD_IT
PWRHOLD signal rising edge
PWRON is low during more than the long-press delay: tdPWRONLP (can be disable though
PWRON_LP_IT
register programming).
PWRON is low while the device is on (running in ACTIVE and SLEEP state) or PWON was
PWRON_IT
low while the device was off (causing a device turn-on). Level-sensitive interrupt
The battery voltage rise above the VMBHI threshold: NOSUPPLY to Off or Backup-to-Off
device states transition (first battery plug or battery voltage bounce detection). This interrupt
VMBHI_IT
source can be disabled through EEPROM programming (VMBHI_IT_DIS). Edge-sensitive
interrupt
The battery voltage falls down below the VMBDCH threshold(running in ACTIVE and SLEEP
VMBDCH_IT
state, if enabled programming VMBCH_VSEL). Edge-sensitive interrupt
GPIO0_R_IT
GPIO_CKSYNC rising-edge detection (available in ACTIVE and SLEEP state)
GPIO0_F_IT
GPIO_CKSYNC falling-edge detection (available in ACTIVE and SLEEP state)
INT1 signal (active low) warns the host processor of any event that occurred on the TPS65910 device. The host
processor can then poll the interrupt from the interrupt status register via I2C to identify the interrupt source. Each
interrupt source can be individually masked via the interrupt mask register.
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2010–2011, Texas Instruments Incorporated