122-28176 Parallax Inc, 122-28176 Datasheet - Page 202

• Manufacturer Part Number: 122-28176
• Description: GUIDE STUDENT PROCESS CONTROL
• Manufacturer: Parallax Inc

Specifications of 122-28176

• Accessory Type: Manual
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Propeller Education (PE) Kit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

Consider (but do not build) the schematic in Figure 6-7. What effect would it have on the
resolution?
Recall that the op-amp is configured in a non-inverting configuration where the gain is:
For the given values, the gain is:
For the potentiometer range of 0 to 5 volts, this would provide an output of 0 to 20 V
(providing that the op-amp was powered from a voltage above 20 V). The ADC is still
converting the voltage range of 0 to 5 V to a byte count of 0 to 255. Consider what
occurs to the slope of the graph in Figure 6-8 of sensor voltage to voltage ADC and byte
value when gain is applied.
R
30 kΩ/10 kΩ + 1 = 3+1 = 4
f
/R
i
+ 1
Figure 6-7
Voltage Monitoring
With Gain
DO NOT BUILD