Wiring for bmp180

Other Hardware Sensors
1

Hello,

My bmp180 has five pins. One is labeled 3.3 and one is labeled VCC. Could someone please tell me if I connect 3.3 V from the Arduino Uno to the pin labeled 3.3 or to the pin labeled VCC? The remaining pins SDA, SCL, GND are simple to wire.

Thanks!

Bruce

2

That is probably a module with a voltage regulator. Don't connect the 3.3V. Connect Aduino 5V pin to VCC.
If it doesn't have a voltage regulator, the BMP180 gets damaged with 5V. Can you give a link to your BMP180 module ?

3

Hi,

I purchased the sensor from Amazon. Here's the link. Note, it's the uxcell model, selling for $5.34.

thanks.

4

Just in case the Vcc isn't for 5V, why not just use 3V3 from Arduino onto the module's 3V3 pin, just to be safe?

5

The black component with 5 pins is the voltage regulator. It's input is VCC, and it's output is for the sensor and also available at the "3.3" pin.
The small black resistors with "472" are pullup resistors for SCA and SCL.

I think both options are okay. Either Arduino 5V to "VCC" or Arduino 3.3V to the "3.3".
Run the i2c_scanner, and it should be detected : Arduino Playground - I2cScanner

I doubt if it is made by excell. I think it is a module made in China without brand.
The BMP180 itself is a very accurate and very good sensor made by Bosch of course, unless it is fake.
The module costs 1.66 dollars here : http://www.ebay.com/itm/161668442507
The BMP180 sensor itself costs 2 dollars (when 5000 are bought).
So, is it fake or not ?

6

..same library as BMP085

7

Thanks, everyone, for the suggestions. I think I'll connect the Arduino 3.3 V to the pin labeled 3.3.

Bruce