Part Number: OPA593
Tool/software:
How fast is OPA593 responding to a change on E/D pin? I am looking to generate 500us current pulses (using a Howland pump implemented with OPA593) and contemplate the idea of switching the output ON/OFF using the E/D pin, as opposed of doing something at the input.
Thanks
Hi Cezar,
Interesting idea, yes this should work so long as you are okay with the output going Hi-Z when disabled.
The E/D pin will still have some delay in activating the output stage as shown in the table below:
Furthermore, there will be some amount of time for the amp to return to a linear operating state.
Figure 6-71 is helpful for understanding what a typical response may look like:
Note, this enable/disable circuitry may have undefined output during the transition from one state to the other. You can see a short transient as the OPA output is being disabled in figure 6-71.
To summarize, yes this method can likely work for somewhat short pulses. Realistically, the E/D delay should always be slower than just using the input stage to change the output signal. For the fastest response, I would use a change in VID to create the pulse.
Thanks,
Jacob
