28176 Parallax Inc, 28176 Datasheet - Page 166

• Manufacturer Part Number: 28176
• Description: KIT PARTS PROCESS CONTROL W/TEXT
• Manufacturer: Parallax Inc

Specifications of 28176

• Accessory Type: Process Control
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: BASIC Stamp® 2 and Board of Education
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

The resolution of a system can also be defined in percentage, where:
So, for a range of 5 V, the smallest change is 0.392% of 5 V, or .0196 V. Note also that
this value is equal to the inverse of the number of steps in percent:
It is important to note that the voltage remains relatively constant during sampling. Once
charged, the stored electrons have little place to go, but given sufficient time they will
dissipate. Test the stability of the voltage by performing the following:
Figure 5-12 Measured Voltages and Various PWM Value Control Settings.
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%Resolution = (Smallest Change/Total Range) x 100%
%Resolution = .0196 V/5 V x 100% = 0.392%
%Resolution = 1/255 x 100% = 0.392%
Set the PWM Value control to midrange.
Set the number of samples to maximum.
Monitor the voltage over the 255 samples.