6.4.3 Suppressing Specification Generation

In section 6.3 Using Jumpers, you modified the schematic with a jumper symbol, thereby setting the output voltage to 600mV. As a result, the test failed to meet specifications because the output voltage was considerably out-of-range. For cases like this, DVM has an option to disable specification checking using the NoSpecs() function.

This function takes a single argument that is the reference designator for the specification that you want to suppress.

To add the three Suppress functions, NoCurves(), NoScalars(), and NoSpecs(), follow these steps:

1. Open the testplan from  SIMPLIS_dvm_tutorial_examples.zip at this path: testplans/6.3_jumpers.testplan.
2. Add three Suppress columns between the Jumper and Source columns.
3. Copy the last six rows and paste them at the bottom of the table.
4. In each of the last three rows in this new set of tests, add the following functions in the three Suppress columns:
   • NoCurves(DVM ILOAD)
   • NoScalars(INPUT:1)
   • NoSpecs(OUTPUT:1)
   Result: The testplan with changes in red should be similar to the following testplan, which is available from  SIMPLIS_dvm_tutorial_examples.zip at this path: testplans/6.4.3_nocurves_noscalars_nospecs.testplan.

To generate reports from this test plan, follow these steps:

1. Open the schematic from  SIMPLIS_dvm_tutorial_examples.zip at this path: LTC3406B/6.3_LTC3406B - DVM ADVANCED.sxsch.
2. Run the three 50% load tests on this schematic.
   Result: The overview report shows a comparison of the three tests.

   • The first test, which is at the nominal designed output voltage, passes as expected.
   • The second and third tests have the same electrical circuit with the output voltage set to 600mV, but the testing is different.
     • The second test fails because the specs are from the nominal output voltage of 1.505V while the converter circuit is configured to regulate at 600mV.
     • The third test passes because you suppressed disabled specification checking on the output voltage level with  NoSpecs(OUTPUT:1).
   • In the test report, the gain_margin and phase_margin specifications are still checked; only the specification checking on the DC output voltage level was disabled with  NoSpecs(OUTPUT:1).
   • In the same test report, there is no ILOAD curve on the second graph since this was removed from the graphical image with the NoCurves(DVM ILOAD) function; however, the curve with all the vector data is included in the simplis_pop3_113.sxgph file.
   • Finally, the scalar measurements for the input source (VSRC and ISRC) have been suppressed by the NoScalars(INPUT:1) function.