Dear all,
I am using UCD3138 in my converter. At low input voltage and light load, everything is fine. However, when I increase the input voltage, UCD stops all DPWM signals. I guess connection gets lost, because after the DPWMs stop, I have no access to memory debugger. I think this problem is caused by noise but again I have a need of help to determine whether it's caused by noise or some other software issue.
I am using software of non-isolated bi-directional converter with UCD3138 Integrated Digital Controllers but I changed almost all the configurations, DPWM settings etc. All I didn't change the parts of software are software interrupt, pmbus_handler, init_variables and init_pmbus functions.
During my tests, in order to eliminate the effect of all ADCs and EADCs, I isolated corresponding measurement circuits from UCD and I pulled the all ADC and EADC pins to the ground. Still problem exists. Then I thought that the problem may be caused by noise on PMBUS pins or by-pass pin or reset pin. I am not expert but the noise on that pins should not be so effective. I attached scope screens of noisy points at the switching. If you check them, I would be glad.
Or the connection gets lost because of the software parts? I am sure I disabled all the faults but again, I dont know what is going on in software interrupt or other functions that I mentioned above. Is there any effect of those functions to disable DPWM signals or reset the device?
I would be appreciated if you help me to solve it.
Thanks
Merih
1.8 V By-Pass Pin:
RESET PIN:
PMBUS_ALERT:
PMBUS_CLK:
PMBUS_CTRL:
PMBUS_DATA:
