Hi..
sitting here with an application board, I wondered how stable my multimeter was in comparison.
So, I put it across a 5v rail on the board.
I noticed it was dipping by 0.02v every 5 secs. That's odd I thought.. I thought my multimeter would be stable, and why so regular ?
Then I noticed the dips coincided with an LED turning itself on and off on the board I was testing the 5v rail on.
then I thought..
0.02v on a 5v rail,.. presuming my multimeter is ok, that LM7805 (that's creating the 5 volts) is only holding the rail to within 0.4%.
Is it some such ? also 0.02v is pretty small in the real world when applied.
Hi, I'm using a PCF8591 to read voltage from a sensor(0 to 5V) and then display it via my MBED on the pc using tera term. The voltage is reading correctly, but at random it displays a wrong value....as shown below.(data upto 6 decimal places is necessary)
the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.394531 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.375000 the voltage is 4.394531
The MBED code I have written is as below
How can i rectify the error. i.e. only one constant value needs to be read.