Vicor Full-chip PRM-RS Customer Board - Manual (Page 15)

UG:009 vicorpower.com Applications Engineering: 800 927.9474 Page 15
9.4 PC Enable / Disable Timing
1. Connect input source and load. Set to OFF.
2. Set PC enable switch (S01-2) to the right position to disable the PRM ® module.
i. PC should be connected to SG.
3. Connect scope probes to PC, V
OUT
, and any other signals to be measured.
4. Set scope scales appropriately.
i. 1 msec / div recommended.
ii. Trigger on positive edge of PC.
5. Apply desired startup load.
6. Apply nominal input voltage (V IN(NOM) ).
i. Verify unit is disabled.
7. Move S01_2 to the left position to enable the device.
8. Record Enable waveform. Adjust scales as necessary.
9. Trigger on negative edge of PC.
10. Move S01_2 to the Right position to disable the device.
11. Record Disable waveform. Adjust scales as necessary.
12. Monitor for switch bounce. Repeat measurement or adjust setup as necessary.
9.5 Current Limit
Note: In order for this test to be performed properly, a resistive load must be used. This
includes an electronic load set to constant resistance mode. Be cautious of potential load
interactions when using electronic loads. If the output voltage or current begin to
oscillate, repeat the test with a passive resistive load.
1. Apply input source and load. Set to OFF.
2. If using an electronic load, change to Constant Resistance mode.
3. Connect DMMs to measure V OUT , IF, and any other signals to be measured.
i. Use electronic load reading, clamp on DC meter to measure approximate output current or
calibrated shunt for more accurate measurement.
4. Set S01_2 to Left position to enable the device.
5. Apply input voltage. Verify output is present.
6. Enable load. Gradually ramp up current (decrease resistance) until current limit threshold is
reached.
i. Current will remain at maximum, output voltage will fold back.