I'm not quite sure about the voltage and current that my Xbee (series 1 with transmit power 1mW) will take when it is plugged into the Xbee Shield and then on top of the Arduino. Is the voltage and current taken from Xbee for transmitting are 3.3V 45mA, or the readings will have huge difference?
Your help and advice are kindly needed. Thanks!
The XBee is powered by 3.3V. When transmitting, it draws up to 35mA to 45mA (depending on mode).
or the readings will have huge difference?
What readings?
I mean the reading between the ideal voltage current and the real voltage current which is measured.
And one thing I don't quite understand, is the transmit current dependant on the length of data bytes which will be sent? For example Xbee series 1 transmit current is 45mA stated in datasheet, but if you transmit only an alphabet to coordinator will it consume much lower current? How does it vary?
Voltage and current are two different things.
The XBee requires 3.3V to operate, regardless of what it's doing.
It requires a certain amount of current, depending upon what it's doing. While receiving, it requires relatively little. While transmitting, it requires more. In sleep mode, it requires quite a bit less.
It will require the transmit current as long as it is transmitting. If you transmit a single character, it will require that current for the length of time it takes to transmit that character. If you transmit a book, it will require that amount of current quite a bit longer.
The amount of current it requires to transmit does not depend upon the character being transmitted. It also does not matter who the data are being sent to (except that if more retries are required to send the data, it will need to transmit for a longer time to get through).
Thanks for your advice. It's actually the time and charge that will vary upon the data length. This has given me an idea to install a specific capacitor size before Xbee to resume the wireless connection even if the electrical falls out.