# Developping an electronic circuit to read out a load cell

Discussion in 'Homework Help' started by tesnime, May 23, 2015.

1. ### tesnime Thread Starter New Member

May 23, 2015
5
0
Hello everybody,
We are still pupils who are trying to paticipate in a contest.

We know that it is too much to ask, but we would appreciate if you could help us especially with the SPICE Simulation!

1- Output voltage: 0-5v for a load of 0..100Kg.
2- The whole circuit should be supplied by two 9v batteries.

PS: the components have to be real (non ideal).

Part one:

Our questions are:
1- how can we minimize the effect of temperature on the output signal?
2- how can we improve the linearity of the output characteristic?
3- how can we improve the temperature dependency?

Part two:
As we want to evaluate Uout = f(Weight) at various temperature and the static operationg point at a specific load it woul be resonable and beneficia to do a SPICE simulation. The problem is, we have no idea of this tool and are not sure f we could make it at time if we start learning it know.
So we wanted to ask if any of you could show us an example with the spice tool so we don't invest much time on it because it is just a little part of the project!

We thank you very much!

File size:
39.5 KB
Views:
15
File size:
77.2 KB
Views:
10
File size:
7.6 KB
Views:
14
2. ### DickCappels Moderator

Aug 21, 2008
3,825
1,041
Please show us what you have done so far.

3. ### tesnime Thread Starter New Member

May 23, 2015
5
0
First of al we would like to thank you for your will to help us Sir. We appreciate that!
We don't know how to inpose an output of 0..5V for a load of 0..100Kg and are not sure how to dimension our components, R and C.
The second problem is, we don't really know how to convert to ADC, should we do that with a dual slope converter or a sigma delta converter. We heard that Spice has such a tool, does it ?
We have to build this, but before doing that have ti simulate that with spice and answer the theoretical questions first.

We would be really glad if you can guide us Sir!

With all our respect.

File size:
40.9 KB
Views:
17