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See GPS Module with Antenna . My doubt is whether the module specified here will exceed the current limitations of RPi, if so how can i interface this to RPi? what is the current rating so that i can use it on Pi without fuss. can i use emitter follower configuration of bjt to boost up the current to meet the gps module' current requirement?

sraok
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Ruthvik Vaila
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  • you should get any recent USB module, BU-353 comes to mind as proven to work and giving reliable results. – lenik Oct 29 '13 at 07:37
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    possible duplicate of [How do I attach a GPS receiver?](http://raspberrypi.stackexchange.com/questions/547/how-do-i-attach-a-gps-receiver) – lenik Oct 29 '13 at 07:39
  • @lenik i am concerned about current the gps shield uses module in above link uses 55mA, so will it create any fuss? – Ruthvik Vaila Oct 29 '13 at 09:09
  • @lenikI edited the post can you please throw some light on it? – Ruthvik Vaila Oct 29 '13 at 14:42
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    That module needs to be connected to the 3.3V line. Some say the 3.3V line can supply up to around 50mA. But that is when the Pi is drawing full power itself (100% GPU + 100% CPU + Ethernet), so typically it more than 50. The 3.3v regulator itself is rated at 1000mA, but since it doesn't have a heatsink, it would probably blow up at that current. All in all, I think you'll be fine with 55mA @ acquisition, 40mA @ tracking. – Gerben Oct 29 '13 at 15:59

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  1. regarding the GPS module, please, see my comment above. BU-353 is cheap, reliable and proven to work. interfacing something else with TTL level shifters from 5V to 3V3 and back is troublesome and eventually will lead to pain and frustration, possibly including burnt unit and/or RasPi.

  2. Raspberry Pi has no output power limitations. There's a polyfuse, that limits the total current to something about 1.2A, thus, considering RasPi consumes about 0.7A, you have about 500mA to play with (~10 times what you need). Still, if you shorten the polyfuse and attach a good power supply you may easily pull the current in excess of several amperes, provided the PCB traces won't burn.

lenik
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