5 volt pressure sensor

I want to measure barometric pressure and need to use 0-5 v

i was going to use the bmp085 - now it has arrived i now realise its 3.3 v and also 12c

does anyone know if a 0-5 volt barometric pressure sensor ?

thanks in advance

Don't give up on the sensor you have! The $10 power supply unit from Sparkfun would solve half your problems.

http://www.sparkfun.com/products/114

I hope some other forum member can explain how you would interface the signals to and from the device to a 5v Arduino...

The web site says:-

User selectable Vcc (3.3V or 5V)

I'm missing something, Mike! What website?

I went back to the Sparkfun page, looked around, looked at the "Quickstart guide" for the breakout board... it says "Pay special attention to how you power the BMP085. Its maximum supply voltage is 3.6V. So don't go feeding it 5V!", by the way!

=== And, perhaps answering my own question about level shifting the data lines... does anyone know if....

http://www.sparkfun.com/products/8745

... is the answer?? (I haven't done enough with I2C stuff to know...)

thanks for the links on the sparkfun logic level convertor and power supply :)

in his case i can not use 12C as a protocol


does anyone know if this sensor is accurate enough to measure baro pressure ?

http://www.coolcomponents.co.uk/catalog/product_info.php?cPath=36_68&products_id=739

I'm missing something, Mike! What website?

http://www.quadroufo.com/product_info.php?products_id=61

Ah! Enlightenment!

There's an interesting note at LadyAda on the device, along with some information about the "using 3v3 devices on a 5v Arduino"...

http://www.ladyada.net/learn/sensors/bmp085.html

While the jumper select of Vcc on the breakout from QuadrpUFO is tempting, it is a little worrying that thier product turns up nothing useful on a hasty Google search. The QuadroUFO "notes" leads to a parts list showing the device at $20, vs the current $28.50. There's not even anything I could find to tell me which link to close to elect 5v or 3v3....

Nor am I clear about what the effect of the jumper would be on the voltages of the signals. Using 3v3 on a 5v Arduino, AS LONG AS there are no 5v I2C components also on the I2C bus seems "do-able"... but a little kludgy...

Ah well, if it were easy, everyone would be at it.

Nor am I clear about what the effect of the jumper would be on the voltages of the signals.

As I2C lines only pull down the voltage selection on the board will only matter if it has a pull up resistor on it.

To use a 3V3 I2C device on a 5V system you need a pull up to 3V3 of about 2K7 on both the clock and the data lines. You also need to modify the library slightly to stop the turning on of the internal pull up resistors.