.OP point found by inspection related error in LTSpice

Question

Hi, I'm an student and I'm trying to make a simple full bridge rectifier with a load resistor and a capacitor. The simulation works with a 1uF capacitor, but when I change it to a 10 uF capacitor the simulation fails with this log: 
 Start Time: Fri Apr 18 20:41:15 2025 solver = Normal Maximum thread count: 6 tnom = 27 temp = 27 method = trap .OP point found by inspection. Singular matrix: Check node n003 Iteration No. 1 Total elapsed time: 0.000 seconds. Singular matrix: check node n003 Iteration No. 1 
 And I don't understand the problem, since it works with a 1uF problem. How can I solve it?

TP2 Ej13.asc

dmercer · Accepted Answer

Hi: You are using the default, simple diode model. I changed the four diodes to use the 1N4148 model from the library and the simulation runs perfectly. It would seem that it is a good idea to always pick an actual diode (model) when running simulations even of very simple circuits like this. Of course, the 1N4148 will not always be the appropriate model to use depending on the application (Power, current required etc.). But in this simple case it is a good pick.)

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.OP point found by inspection related error in LTSpice