nRF9160 DK v1.0.0

I/O expander

The nRF9160 DK has an I/O expander that can optionally be used to interface the LEDs, slide switches, and buttons.

The connection of each component is controlled by the nRF52840 using analog switches (see Switches for buttons and LEDs). The I/O expander can be enabled by the nRF52840. See Switches for I/O expander. When the I/O expander is enabled, the I/O expander is interfaced by the nRF9160 GPIOs shown in the following table.

Table 1. nRF9160 I/O expander interface
Signal GPIO Description
SDA P0.30 I2C data line
SCL P0.31 I2C clock line
IOEXP_IRQ P0.06 Interrupt line from the I/O expander
The following table shows the I/O expander connections:
Table 2. nRF9160 I/O expander connections
Component I/O expander pin
LED 1 I/O_EXP_IO4
LED 2 I/O_EXP_IO5
LED 3 I/O_EXP_IO6
LED 4 I/O_EXP_IO7
Switch 1 I/O_EXP_IO2
Switch 2 I/O_EXP_IO3
Button 1 I/O_EXP_IO0
Button 2 I/O_EXP_IO1
Figure 1. I/O expander
Schematic: I/O expander