Yoctopuce Yocto-GPS, User Manual

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order to prevent any power consumption check in the operating system). This looks a bit dirty, but
given the fact that computer USB ports are usually well protected by a hardware current limitation
around 2000mA, it actually works in every day life, and seldom makes hardware damage.
What you should remember: if you connect Yoctopuce modules through one, or more, USB hub
without external power supply, you have no safe-guard and you depend entirely on your computer
manufacturer attention to provide as much current as possible on the USB ports, and to detect
overloads before they lead to problems or to hardware damages. When modules are not provided
enough current, they may work erratically and create unpredictable bugs. If you want to prevent any
risk, do not cascade hubs without external power supply, and do not connect peripherals requiring
more than 100mA behind a bus-powered hub.
In order to help controlling and planning overall power consumption for your project, all Yoctopuce
modules include a built-in current sensor that tells (with 5mA precision) the consumption of the
module on the USB bus.
4. Assembly and connections
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