Tool/software: TINA-TI or Spice Models
Hi,
I came across an issue when using the TPS7A4001 transient model in TINA-TI.
The problem, or strange behaviour I see is this. When I analyse the various currents in and out of the model. They do not add up. That is as soon as the input voltage rises above the output voltage the current into the device continues to rise linearly, even though the output current has stabilised according to the load impedance. Even if I measure individually all the possible current paths in and out of the model I have a huge discrepancy.
I have attached an example TINA simulation if you would like to take a look. Where is the current going? It suggests that somehow the model has a path back to the voltage source invisible to the pins on the device. In fact invisible to any connection in the schematic. To pot it bluntly this is impossible. Am I making some stupid mistake? It also suggests that if I where to use this TPA7A4001 as an ~38V output regulator on a 60V input supply and where to draw ~3.8mA from it. The total input current shows as ~22mA @60V. This would suggest that the power dissipated in the load would be ~140mW but the power consumed from the input supply is 1.32W rather than the 228mW I would have expected.
Any help to better my understanding would be appreciated. This is making my larger simulation quite unrealistic.
Thanks
Aidan
