18 lines
1.2 KiB
Markdown
18 lines
1.2 KiB
Markdown
# load-cell-test
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**Engineer Responsible for this Section: Willow Herron**
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**Section README Authored By: Katherine Sarna**
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Datasheet:
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- MCP-6006 (Operational Amplifier)
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- ADC101C021CIMM (I2C ADC)
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Purpose of load-cell-test: We want to see how much water is left in the water supply used for the greenhouse garden, so we can be frugal and efficient about how much water the garden uses. This test reads the weight of the remaining water.
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The load cell we chose is a wheatstone bridge with 2 kOhm resistance (+-20 Ohms). The wheatstone bridge has deflection, so when you apply a load to the load cell, 2 of its resistors go up by 20 Ohms, and 2 go down by 20 Ohms, hence the +- 20 Ohms. This load cell is amplified to a signal (range) of ~0-3.3V. The load cell is put into an I2C ADC in order to read the value of the water weight to the daughterboard or control board. This is how we determine how much water has been used and how much is left in the water supply for the greenhouse garden management system.
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- I2C: Inter-integrated circuit, communication protocol
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- ADC: Analog to digital converter
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As far as design considerations, in order to maximize analog signal integrity, we tried to keep sensitive analog traces as large/wide and as short as possible.
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