Want to improve your testers performance?
...here are some points and steps you may consider.
Getting the right measurement point
- Ouput Voltage Measurement - connect the twisted shielded cable right at the point on the mating connector of the UUT.
- AC Source voltage sensing - a remote sense connection is required to eliminate voltage drop. Sense cable should be a twisted pair cable. This should be connected right at the mating connected of the UUT input plug. Make sure also that the equipment is set for remote sensing.
- DC Source voltage sensing - a remote sense connection is required to eliminate voltage drop. Sense cable should be a twisted pair cable. This should be connected right at the mating connected of the UUT input plug. Make sure that the equipment is set for remote sensing.
- Measuring Ripple and Noise - use a shielded coax cable or a scope probe. Connect this probes at close as possible to the point you want to measure.
Test Time Optimization
- Test Time optimization is very important for the matured product. After a passed CPK and GR&R result, a test software needs to be optimized to increase test capacity. Doing a test time optimization is very critical in the sense that you might not get the right measurement. It is recommended to do GR&R prior and after doing the test time optimization to make sure that measurement were not affected.
- Here are some tips and steps in doing test time optimization.
- Run a GR&R for the specified product. Make sure that GR&R is passed before proceeding.
- Study each test, analyze its test condition but load and line conditions.
- Group all the test that has same input condition
- Then group test with same load condition.
- Mark the tests that requires turn on measurement, like rise time, turn on delay and start up delay.
- Mark the tests also that requires turn off measurements, like hold up time and turn off delays.
- Now arrange the test in such a way you will minimized the change of condition.
- Also, set the first parameter condition and equipment setting during the operator loading time.
- Here's some example
- Rise time with input condition A, Load Condition A. Measure regulation. Measure ripple and noise. ...measure other test with line condition A. Do Hold up time.
- Start up time with line condition B, load condition B. Measure regulation. Measure ripple and noise. ...measure other test with line condition B. Do Turn Off Delay.
- This is only an example, you can arrange it in a way to reduce the condition change over time.
Remote Sensing on Input source
The advantage of using remote sensing:
This is very important to have a desired voltage at the end point or in the terminal of your fixture or at the terminal of your UUT. All the power supplies right now has a remote sensing option. Using the remote sensing connection, you will be sure that the voltage drop from the wire to your load will be compensated.
Please refer on the illustration below:
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