Jack Frost has settled into Toronto for the season, and the season of giving has given many people new electronic devices. For many recipients, a new cell phone, tablet, or computer is an upgrade. There are also those who are receiving a portable device for the first time. In the recent years, consumers have discovered that some models of smartphones would turn off when the temperature dropped too low and the battery stopped functioning. Soon after, questions arose asking whether extreme cold temperatures could also damage the circuit board in new devices. The urban myth suggests that electronic circuit boards would expand and contract from extreme temperatures, causing it to crack.
During the process of electronic circuit board assembly, the electronic components are coated with a silicone or urethane, keeping moisture away from the circuitry. This silicone or urethane coating keeps the equipment running, but is not immune to salt water or corrosive elements.
Electronic circuit board assembly is rated to operate at optimal levels within the temperature range of the equipment it will be a part of. For example, electronic circuit board assembly for the military ranges between the temperatures of -55 degrees Celsius to +125 degrees Celsius, while the industrial and automotive temperature range is -40 degrees Celsius to +85 degrees Celsius.
Electronic circuit board assembly for commercial and consumer electronics has the temperature range of 0 degrees Celsius to +70 degrees Celsius. Although a smartphone will be operational if it is outside in below freezing temperatures, it could slow down and eventually shut down if exposed long enough to sub-freezing temperatures. If all the components within the device drop to temperatures below freezing, it would be better to let the device thoroughly warm up to room temperature before turning it back on.
Exposing a device to sub-freezing temperatures for extended periods of time is still not recommended. During warm-up, condensation could form within the device. Although solder mask and the silicone or urethane coating applied during electronic circuit board assembly protects parts of the printed circuit board (PCB), it does not protect the other components or the rest of the device. Keeping your smartphone in your pocket is a safe way to keep your device working outdoors at optimal levels all through winter.