LTE modem coexistence interface

LTE modem uses a dedicated three-pin interface for RF interference avoidance towards a companion radio device e.g. an external positioning device or Bluetooth® Low Energy device.

The inputs and outputs for this interface:

Note: COEX2 pin requires an external pull-down resistor in 100 kΩ size range to be used.
Note: Please refer to nRF9160 modem firmware release notes found under nRF91 FW binaries downloads concerning availability of COEX signaling feature support".
COEX interface timing in relation to modem state is shown in the figure below.
Figure 1. COEX interface timing
COEX interface timing