Power question on bluetooth module

Using Arduino General Electronics
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Hi guys, i'm new to the fourms and am kind of a rookie with electronics but am trying to make my first hardware project.

I bought this bluetooth module for connecting my iPhone to arduino, and in the picture below there is a list of specifications of it.

So my assumption is that the only description I should really care about is #10, Power.

What exactly does this mean +3.3Vdc 50mA?

I am completely familiar with volts and amps but i'm confused with what these are telling me. Does it require 3.3V and 50mA or are these the maximum that the bluetooth can handle without breaking?

Any help is appreciated! Thanks

Also while i'm posting, how can I just show the picture on my post without making everyone click on my image.

BluetoothQuestion.png
BluetoothQuestion.png734×538 298 KB

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It means you have to apply 3.3 volts to the power pins and the module will take no more than 50mA. Sometimes it will take less, like when it is not sending, but the most it will ever take is 50mA.

The voltage means that any signal you send to it from the Arduino must not be greater than this voltage, so if you are using a 5V Arduino you have to use level shifting components.

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Ok great thank you!

Also, I accidentally connected this module to the Arduino (all pins, vcc, gnd, tx and rx) and the Arduino had output 5V to it. Now the Arduino is no longer recognized by my computer, could this have killed my board?

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EricSutton:
Ok great thank you!

Also, I accidentally connected this module to the Arduino (all pins, vcc, gnd, tx and rx) and the Arduino had output 5V to it. Now the Arduino is no longer recognized by my computer, could this have killed my board?

Anything can happen if you do something stupid. If the overvolt made the module fail short, it could have easily dragged down the chip or some part of te power supply with it.

Plug it into USB, then whip out a multimeter (you do have one, right?) and measure the DC voltage across pins 2 and 6 on the 2x3 male header on the end of the board.

Do you measure 5V (give or take 10%) across those pins?

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You might have blew the 5v regulator on the arduino as Jiggy-Ninja says check the 5v output

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So i measured pins 2 and 6 as you said and measured 4.98V, so basically 5V.

Also, the Tx and Rx lights are always on when I plug in the USB, not sure if that means anything but it used to not be like that.

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