122-28176 Parallax Inc, 122-28176 Datasheet - Page 207

• 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

How would the 0.7 V be set? One way would be to use a potentiometer that is adjusted
to 0.7 V as the input for V
the voltage range of interest.
Fortunately, the ADC0831 converter can directly perform the spanning and offsetting.
Consider the pin-out of this device as shown in Figure 6-12.
Up until now Vin(-) has been connected to Vss (0 V) and V
(5 V). These two inputs set the offset and span voltages over which to convert. If the
ADC0831’s Vin(-) is set to 0.7 V and Vref is set to 0.5 V, the ADC will convert the range
of 0.7 V to 1.2 V to a byte value of 0 to 255 respectively.
I2
. In both configurations we are setting the offset and span for
ref
Figure 6-12
ADC0831 Pin Out
has been connected to Vdd
Figure 6-11
Offset and Gain
using Differential
Configuration
DO NOT BUILD