User's Manual

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HW Design Guidelines
transfer heat.
If systems with M18QF/M18QA Series modules embedded intend to work under
ambient temperatures as low as -40°C, it’s suggested that:
1. SIM Card need to be well arranged to make sure it is functional at the
condition of ambient temperature as low as -40°C.
2. Adding heating circuit on board design, the circuit mainly consists of
temperature sensing unit, heating element and control unit.