2573 - PAC Designer: How does the DC-DC Converter library work with the TRIM resistor calculation in PAC-Designer when a project is opened but does not have access to the original DC-DC Converter library?

2573 - PAC Designer: How does the DC-DC Converter library work with the TRIM resistor calculation in PAC-Designer when a project is opened but does not have access to the original DC-DC Converter library?

Solution: When a user creates a new item in the DC-DC Converter library an .XML file is created and saved in the "PAC-Designer\DCtoDC_Library" folder. Then when the user configures each Trim output, they must Import a DC-DC converter into the design from the library files. Importing the converter into the design (and saving the design) causes a certain amount of information to be stored with the design in the PAC file. The information that is stored is not the entire .XML file but rather a subset of that information. Once the DC-DC converter has been imported into PAC-Designer's Trim window, the software uses the information from the PAC file to update the Target Voltages, Trim Resistor sizes, Realized Voltage, DAC code, and DAC current values that are displayed in the window. The Target Voltages generally need to be updated by the user after the DC-DC is imported. Once the user updates the Target Voltages for each of the voltage profiles and clicks the calculate button, then the software updates the Trim Resistor sizes, Realized Voltage, DAC code, and DAC current values that are displayed in the window. You will notice that if a different DC-DC converter is imported the Target Voltages get overwritten with new values as the software updates all the values. If the design is saved with one result and then is loaded into a different copy of PAC-Designer the software will use the information in the PAC file. If the user updates the Target Voltages the software will update the Trim Resistor sizes, Realized Voltage, DAC code, and DAC current values once the calculate button is pressed. The resistor sizes may be updated or not depending upon how much of a change is made in the Target Voltage values; for small changes the resistor sizes may net be affected. If the Target Voltage changes are too great the software may not be able to generate a valid solution. The user can return to the original values of Trim Resistor sizes, Realized Voltage, DAC code, and DAC current by hitting cancel or by returning the Target Voltages to their original values. This behavior is the same regardless of whether the design is loaded into a different version of PAC-Designer (or the same version on another PC) that does NOT have the same converter in the DC-DC library or if it does have the same DC-DC converter in the library. The data in the PAC file that relates to this DC-DC converter stays the same until another DC-DC converter is Imported into the design for this Trim output. It is possible for users to have different versions of the .XML files in their libraries that contain different configurations of the DC-DC converter. If this occurred and a user thought their converter definitions were the same, then when they loaded the file into PAC-Designer, Imported the DC-DC again, and set the Target Voltages to the same values used previously they could still get different resistor sizes, DAC codes, and DAC currents. This would happen because the DC-DC converters configurations are in fact different between the two files.