LT3083 portable supply

[pjwl]

Hello,

I'm trying to make my own uSupply with the LT3083, I would like to have 0..5V output with 0..2A.
After studying the forum: uSupply - LM350T instead of LT3080 I cam with a similar idea which I did made up in LTSpice



I need to add 1mA load because the LT3083 requires that, but when simulating every seems to work okay.

I was wondering if some has tips and maybe some suggestion for some cheaper opamps.

Thanks
Pjwl

[David Hess]

The LT6220 is not doing anything useful.  Removing it will improve performance of the current control loop and make frequency compensation easier.

The AD8031 is much faster than required for this application.  If a single supply precision part is required, then the LT1013 is both inexpensive and fast enough given the external compensation shown in the schematic.

If you used the AD8031 for higher slew rate to lower switching time between current and voltage control, then the external frequency compensation is defeating that reason.  A slightly different configuration which clamps the output of the inactive error amplifier may be necessary if you want the fastest switching between current and voltage control.