OnCake wrote:After much research I have tried to output 0-10v, but can only get from 2.4-10v with my current setup. Well I can actually go over 11v, but I only need 10v max.
Does anyone know why I might not be getting 0-10v or 1.1mv-10v? Should I use a different op-amp and if so which?
Quoting from this TI bulletin:
The circuit shown is connected as a voltage follower, so the
output voltage is equal to the input voltage. Of course, there
are limits to the ability of the output to follow the input. As
the input voltage swings positively, the output at some point
near the positive power supply will be unable to follow the
input. Similarly the negative output swing will be limited to
somewhere close to –VS. A typical op amp might allow
output to swing within 2V of the power supply, making
it possible to output –13V to +13V with ± 15V supplies.
Figure 1b shows the same unity-gain follower operated from
a single 30V power supply. The op amp still has a total of
30V across the power supply terminals, but in this case it
comes from a single positive supply. Operation is otherwise
unchanged. The output is capable of following the input as
long as the input comes no closer than 2V from either supply
terminal of the op amp. The usable range of the circuit
shown would be from +2V to +28V.
Any op amp would be capable of this type of single-supply
operation (with somewhat different swing limits). Why then
are some op amps specifically touted for single supply
Sometimes, the limit on output swing near ground (the
“negative” power supply to the op amp) poses a significant
limitation. Figure 1b shows an application where the input
signal is referenced to ground. In this case, input signals of
less than 2V will not be accurately handled by the op amp.
A “single-supply op amp” would handle this particular
application more successfully.