Hi
I need to messure on -0.5 to 2 volt.
how can i do that ?
gds
Sten Jensby
You have to “pull” the measured voltage above zero.
You may do this by using a diode and a resistor.
Thanx,
Hope this will work,
rgds
Sten Jensby
And u are sure that the polirity of the diode is correct, i get the same reading regardless if -0,2 og 1 v input.
According to this simulation result you should get 60.55mV to 2.49V to the K8061 input when you connect -0.5V to 2V to the cathode of the diode D1 (1N4148).
If your voltage source (-0.5V to 2V) output impedance is low, you can reduce the resistor R1 to 1k to get better linearity for the K8061 input voltage.
Hi,
When measuring i always get 2,950 v at k8061 ( also with multimeter. )
Need the voltage to be from -300 mv to +100 mv , that will do it.
It’s for messure temperature LM35C. -30 to +10 degrees C.
Datasheet LM35 is here http://www.national.com/ds/LM/LM35.pdf
It seems that the LM35 do not allow a “pull up” resistor to its output.
Here is the solution that should work:
The result is the difference between analog inputs AD1 and AD2.
I then have to few inputs.
i have 3 temp with negative voltage, and 3 only positive,
that’s 9 inputs.
Can i use common for ex AD2, for the 3 negatives ?
even common diodes for the 3 lm35 ?
[quote]Can i use common for ex AD2, for the 3 negatives ?
even common diodes for the 3 lm35 ?[/quote]Yes, you can use common diodes and common K8061 input for the negatives.
The LM35 supply voltage range is 4 to 30 volts. Diodes drop the voltage about 1.4V.
You have to use >5.4V supply Vs.