Figure 9-45 shows the GPIO I/O buffer for all GPIOn pins listed GPIO0-GPIO17 in Pin Configuration and Functions. GPIOn pins can be mapped to USB Type-C, USB PD, and application-specific events to control other ICs, interrupt a host processor, or receive input from another IC. This buffer is configurable to be a push-pull output, a weak push-pull, or open drain output. When configured as an input, the signal can be a deglitched digital input or an analog input to the ADC. The push-pull output is a simple CMOS output with independent pulldown control allowing open-drain connections. The weak push-pull is also a CMOS output, but with GPIO_RPU resistance in series with the drain. The supply voltage to this buffer is configurable to be LDO_3V3 by default or VDDIO. For simplicity, the connection to VDDIO is not shown in Figure 9-45, but the connection to VDDIO is fail-safe and a diode will not be present from GPIOn to VDDIO in this configuration. The pullup and pulldown output drivers are independently controlled from the input and are enabled or disabled via application code in the digital core.

Figure 9-45 IOBUF_GPIOLS (General GPIO) I/O

Figure 9-46 shows the IOBUF_GPIOLSI2C that is identical to IOBUF_GPIOLS with an extended deglitch time.

Figure 9-46 IOBUF_GPIOLSI2C (General GPIO) I/O with I²C De-glitch