@mochensama , Hi, have you solved your problem? I designed the circuit with reference to spec, if you use PSI5-P mode, you shouldn't pull up BH1 of pin8, right? Also are you using 5V for VASSUP? I feel like it's usually with a higher voltage, right? ...

Any update on this? I also want to simulate the PSI5 sensor, and I went through the L9663 datasheet, and found that it can only receive PSI5 data from sensor, but could not send PSI5 frames.  Does ST have such IC could simulate PSI5 sensor?

Hi, I am now trying to choose L9663 to simulate sensor, so how do you simulate sensor finally? Is there any avaliable IC to do this? Thanks.