The output voltage is a proportion of the supply voltage (+V)
In the example shown if
- +V = 12v, then range is 1v to 11v
- +V = 9v then range is 0.75v to 8.25v
- +V = 6v then range is 0.5v to 5.5v
Change R1 and R2 to change the range of voltage.
The output current is very low and should be buffered or connected to a high impedance input - such as a comparator.