Hey,
I'm building around the Bosch BMP085 pressure sensor and planning to use the sensor to measure my quadrocopter's height. The drone is powered by a propietary rechargable battery with 3.7V. The sensor, according to its datasheet, only likes 1.8V to 3.6V. I would like to bring the voltage down to somewhere around 2.5V, considering that the battery will drop in voltage when it's not fully charged anymore.
Now here is my problem: The sensor varies in load from 5µA (in standard mode) to a peak of 1000µA, at least according to its datasheet. I want a voltage drop of about 1.2V across the resistor, so I do some simple, relying on the minimum and maximum current:
1.2V / 5µA = 240k?
1.2V / 1000µA = 1.2k?
If I choose 240k?, the voltage drop will be far too big when the load is at peak, but if I choose 1.2k?, the voltage drop will be far too small. What resistor value should I choose, or is there any other solution to my problem?
I'm grateful for any response, and sorry for my not-so-perfect English.
niasie
Edit: I just saw, that the Greek Omega isn't displayed correctly. The "?" are supposed to mean Ohms.