SLVUCD2 January 2022 TPS65917-Q1
TPS65917-Q1 integrates eight configurable general-purpose I/Os (GPIOs) that are multiplexed with alternative features. This section describes the default configuration of each GPIO, as well as the configuration of internal pullup or pulldown resistors on the GPIOs.
REGISTER | BIT | DESCRIPTION | OTP VALUE | ||
---|---|---|---|---|---|
PRIMARY_SECONDARY_PAD2 | GPIO_6 | Select pin function | REGEN3 | ||
GPIO_5 | Select pin function | POWERHOLD | |||
GPIO_4 | Select pin function | REGEN2 | |||
PRIMARY_SECONDARY_PAD1 | GPIO_3 | Select pin function | SYNCDCDC | ||
GPIO_2 | Select pin function | GPIO_2 | |||
GPIO_1 | Select pin function | RESET_IN | |||
GPIO_0 | Select pin function | REGEN1 |
The GPIO_0 pin is an open drain pin and therefore must be pulled up externally. TI does not recommend pulling the GPIO_0 pin up to any always-on signal such as VCCA or LDOVRTC_OUT. The GPIO_0 pin is configured as an input before the OTP memory is loaded at power up, and pulling the pin up to an always-on rail can cause a glitch on the GPIO_0 pin. Therefore, TI recommends pulling this signal up to a sequenced output, such as SMPS3 (1.8 V) or LDO4 (3.3 V).
Table 3-9 describes the pullup, pulldown, and open-drain settings for the corresponding GPIOs. These settings only apply in GPIO mode (example: GPIO_0), and do not apply to any of the secondary functions (example: REGEN1).
REGISTER | BIT | DESCRIPTION | OTP VALUE |
---|---|---|---|
PU_PD_GPIO_CTRL2 | GPIO_6_PD | Configure pulldown for GPIO_6 | 0: Pulldown disabled |
GPIO_5_PD | Configure pulldown for GPIO_5 | 0: Pulldown disabled | |
GPIO_4_PU | Configure pullup for GPIO_4 | 0: Pullup disabled | |
GPIO_4_PD | Configure pulldown for GPIO_4 | 0: Pulldown disabled | |
PU_PD_GPIO_CTRL1 | GPIO_3_PD | Configure pulldown for GPIO_3 | 0: Pulldown disabled |
GPIO_2_PU | Configure pullup for GPIO_2 | 0: Pullup disabled | |
GPIO_2_PD | Configure pulldown for GPIO_2 | 0: Pulldown disabled | |
GPIO_1_PD | Configure pulldown for GPIO_1 | 0: Pulldown disabled | |
GPIO_0_PD | Configure pulldown for GPIO_0 | 0: Pulldown disabled | |
OD_OUTPUT_GPIO | GPIO_4_OD | Configure GPIO_4 to be open-drain or push-pull | 1: Open-drain |
GPIO_2_OD | Configure GPIO_2 to be open-drain or push-pull | 0: Push-pull |
Table 3-10 describes the polarity settings for each GPIO. These settings apply to both GPIO mode and secondary functions.
REGISTER | BIT | DESCRIPTION | OTP VALUE |
---|---|---|---|
POLARITY_CTRL | GPIO_6_POLARITY | Enable or disable polarity inversion for GPIO_6 | 0: Inversion disabled |
GPIO_5_POLARITY | Enable or disable polarity inversion for GPIO_5 | 0: Inversion disabled | |
GPIO_4_POLARITY | Enable or disable polarity inversion for GPIO_4 | 0: Inversion disabled | |
GPIO_3_POLARITY | Enable or disable polarity inversion for GPIO_3 | 0: Inversion disabled | |
GPIO_2_POLARITY | Enable or disable polarity inversion for GPIO_2 | 0: Inversion disabled | |
GPIO_1_POLARITY | Enable or disable polarity inversion for GPIO_1 | 1: Inversion enabled | |
GPIO_0_POLARITY | Enable or disable polarity inversion for GPIO_0 | 0: Inversion disabled |