Integration Manual

TSD-19090601 - R15 Contents Page 119 of 143
 Optimize antenna return loss, to optimize overall electrical performance of the module including a
decrease of module thermal power.
 Optimize the thermal design of any high-power components included in the application, such as linear
regulators and amplifiers, to optimize overall temperature distribution in the application device.
 Select the material, the thickness and the surface of the box (i.e. the mechanical enclosure) of the
application device that integrates the module so that it provides good thermal dissipation.
Further hardware techniques that may be considered to improve the heat dissipation in the application:
 Provide a heat sink component on the backside of the application board, below the cellular module, as
a large part of the heat is transported through the GND pads of the TOBY-L3 series LGA modules and
dissipated over the backside of the application board.
 Force ventilation air-flow within the mechanical enclosure.
Beside the reduction of the Module-to-Ambient thermal resistance implemented with the correct application
hardware design, the increase of module temperature can be moderated by suitable application software
implementation:
 Enable power saving configuration or the power state manager.
 Enable module connected mode for a given time period and then disable it for a time period long
enough to properly mitigate temperature increase.
☞ TOBY-L3 series modules include a thermal daemon that monitors the internal temperatures by means
of sensors integrated within the module, and it takes actions in order to reduce the module temperature,
implementing a progressive reduction of the maximum Tx RF power, a progressive reduction of the
maximum throughput, a progressive reduction of the processing cores clock frequency, a progressive
shutdown of the processing cores, up to the shutdown of the module.
2.15 Design-in checklist
This section provides a design-in checklist.
2.15.1 Schematic checklist
The following are the most important points for a simple schematic check:
 DC supply must provide a nominal voltage at the VCC pin within the operating range limits.
 DC supply must be capable of supporting both the highest peak and the highest averaged current
consumption values in connected mode, as specified in the TOBY-L3 series Data Sheet [1].
 VCC voltage supply should be clean, with very low ripple/noise: provide the suggested bypass
capacitors, in particular if the application device integrates an internal antenna.