1. TROUBLES WITH SPURIOUS “CURRENT LIMIT” IN REMOTE SENSE OPERATION
G. Visser
7/23/2012
MPOD LV
P/N 0MPV.8008LI
S/N
TROUBLES WITH SPURIOUS “CURRENT LIMIT” IN REMOTE SENSE OPERATION
The first two slides are same as I sent before. Load is 5/3 Ohm resistor, on 100 feet 20AWG cable.

2. Remote sense, ok ≤ 1.9 V
Remote sense, trouble ≥ 1.9 V
?? !!

3. Local sense, both cases as above, setpoint tuned for same load & terminal voltages, all seems to work fine, no spurious current limiting.

4. Here (next slide) is an illustration of open sense connections oddness
Here (next slide) is an illustration of open sense connections oddness. I feel it may be related.

5. At 1.6V setpoint, it’s misbehaving
At 3V setpoint, works as expected

6. Note: all waveforms AC coupled, 10MOhm passive probe
Fast, 5/3 to 5/4 Ohm load
Transient tests
Fast, 5/4 to 5/3 Ohm load

7. Medium, 5/3 to 5/4 Ohm load
Slow, 5/3 to 5/4 Ohm load
200ms/div !
Slow, 5/4 to 5/3 Ohm load
200ms/div
Medium, 5/4 to 5/3 Ohm load

8. Medium, 5/3 to 5/4 Ohm load
With 2x470uF
Medium, 5/3 to 5/4 Ohm load
With setpoint 1.5V
Really current limiting!
Medium, 5/4 to 5/3 Ohm load
With 2x470uF
Medium, 5/4 to 5/3 Ohm load
With setpoint 1.5V

9. ON THIS SLIDE ARE THE WAVEFORMS AT SUPPLY OUTPUT TERMINALS
Medium, 5/3 to 5/4 Ohm load
With 2x470uF
Medium, 5/3 to 5/4 Ohm load
With setpoint 1.5V
Medium, 5/4 to 5/3 Ohm load
With setpoint 1.5V
Medium, 5/4 to 5/3 Ohm load
With 2x470uF