![](/images/new-backgrounds/1166768/16676849x1.webp)
The step size is also referred to as the resolution. Once the step size is known, all that is needed to determine the voltage of an A/D input is the number of steps. The data returned from the 485SDA10 is the number of steps. The voltage at the A/D inputs can be calculated as follows:
Voltage = (# of steps) * (Step size)
Example 4.1 - Assume: A/D Ref. Input + = 5.0V DC and A/D Ref.Input - = 0V DC.
Therefore:
Reference Range = (A/D Ref. Input +) - (A/D Ref. Input
Reference Range = 5.0V DC
Step size = (Reference Range) / 1023 Step size = (5.0V DC) / 1023
Step size = 4.8876 millivolts
Example #1: A/D reading = 1023 (3FFH)
A/D voltage = reading * step size
A/D voltage = 1023 * 4.8876 millivolts
A/D voltage = 5.0 Volts
Example #2: A/D reading = 0
A/D voltage = 0 * 4.8876 millivolts
A/D voltage = 0 Volts
Example #3: A/D reading = 675 (2A3H)
A/D voltage = 675 * 4.8876 millivolts
A/D voltage = 3.2991 Volts
485SDA103798 Manual | 21 |
B&B Electronics
PH (815)