Question
How to measure the threshold value of power supply voltage, input voltage and output current etc.
Answer
The threshold value of power supply voltage, input voltage, and output current are measured using Generic Search IP(PCXA01-M5005). Generic Search IP is an algorithm IP that searches the PASS / FAIL transition point of the execution result while executing the measurement item and changing the value of the variable used in the specified measurement item.
An example of measuring the maximum operating power supply voltage is shown below.
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Define the double type variable for the search. Below, this variable is described as vdd.
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Create functional test items for the search using Functional Testing IP. Specify vdd for [Source Value] of the power supply pin measuring the maximum operating power supply voltage. Also, if there is a parameter whose value you want to change following the power supply voltage such as the input voltage of the IO pin, specify the value with the expression using the variable for the search. ([VIH]=vdd×0.8)
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Search Maximum operating power supply voltage using Generic Search IP.
Specify each parameter as follows. In the following example, the change of the power supply voltage and the execution of the search target test are repeated, and the value at which the execution result was PASS at the last is taken as the search result. If execution results are all Pass within the search range, the value of [Stop Value] will be the search result.Parameter Value Target Item Functional test item created in index.2 Target Variable vdd Start Value Power supply voltage value at which the execution result of [Target Item] is PASS Stop Value Power supply voltage value at which the execution result of [Target Item] is FAIL or search stops. Resolution Measurement resolution Search Method Linear or はBinary Result for no transition point Decided by Execution Result