Huawei ME906s LTE M.2 - Page 34

HUAWEI ME906s LTE M.2 Module
Hardware Guide
Description of the Application Interfaces
Issue 05 (2019-03-25)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
34
Figure 3-18 Connections of the USIM_DET pin
CD is a pin detecting of USIM in the USIM socket, in normal, there will be a detect pin
in the USIM socket.

It is recommended not to add a diode on the USIM_DET pin outside the module.

The normal SHORT USIM connector should be employed. The logic of
USIM_DET is shown as Figure 3-19 . High represents that USIM is inserted; Low
represents that USIM is removed.

When USIM is inserted (hot), USIM_DET will change from Low to High;

When USIM is removed (hot), USIM_DET will change from High to Low;

The module will detect the level of USIM_DET to support the hot swap.
Module
(Modem)
BB Chip
1.8V
USIM_DET
470 pF
USIM Deck
CD
If USIM card is absent, the CD connects to Ground.
If USIM card is present, the CD is open.