Voltage divider from 5v to 3 volts

Status
Not open for further replies.
W

Wayne

Well-known member
Ok, I know how to make voltage dividers, but I need to know the analog input resistance. I see on the pdf for the teensy 3.1 to be either 2 K or 5 K ohms.

I will be measuring a sensor output of near 0 volts to ~ 5volts. This will be related to 0 psi to 3,000 psi. I need to be close since the gauges are in 50 psi steps (I was told).

This is the last part of the product and means nearly done.. No more Saturdays working.

I'm guessing I can put 2 5K's or 2 10K's and sense the center to ground for simplicity.
 
Wayne said:
Ok, I know how to make voltage dividers, but I need to know the analog input resistance. I see on the pdf for the teensy 3.1 to be either 2 K or 5 K ohms.

I will be measuring a sensor output of near 0 volts to ~ 5volts. This will be related to 0 psi to 3,000 psi. I need to be close since the gauges are in 50 psi steps (I was told).

This is the last part of the product and means nearly done.. No more Saturdays working.

I'm guessing I can put 2 5K's or 2 10K's and sense the center to ground for simplicity.
Click to expand...

If you want really good accuracy, use an opamp with unity gain.

Output from sensor -> resistor divider -> opamp -> Teensy
 
Thanks, I will put that into my design. They have not determine the type of sensor yet, but this should take anything as an input since most are around 0-5v
 
Status
Not open for further replies.
Back
Top