LTC3889 VIN over-voltage fault issue

I've already managed to set the outputs VOUT0 and VOUT1. I had not taken into account that RUN0 and RUN1 should be driven with open drain outputs.

The only doubt that remains for me to clarify is the label LTC3886 instead of LTC3889 in the LTpowerPlay.

gschelotto said:

MFR_PADS is referred to LTC3886 instead LTC3889. Why? It is a LTpowerPlay bug?

Any hint?

gaston

Hi gaston,

Apologies for delayed response. For the first question, the reason for VIN_OV_FAULT is that the VIN_OV_FAULT_LIMIT is set as 48V. When powering VIN with a voltage higher than 48V (even if slightly higher than 48V is sensed), VIN_OV_FAULT would be triggered. I would suggest to set VIN_OV_FAULT_LIMIT at about 55V since the max VIN for the demo board is 54V. It works just fine as when VIN=54V and the VOUT, FSW etc are at the default conditions of this demo board.

For the second question, we can also see LTC3886 instead of LTC3889 in the LTPowerPlay when running the demo board. I think it may be a bug but definitely it will not impact the demo board operation.

Hi gaston,

Apologies for delayed response. For the first question, the reason for VIN_OV_FAULT is that the VIN_OV_FAULT_LIMIT is set as 48V. When powering VIN with a voltage higher than 48V (even if slightly higher than 48V is sensed), VIN_OV_FAULT would be triggered. I would suggest to set VIN_OV_FAULT_LIMIT at about 55V since the max VIN for the demo board is 54V. It works just fine as when VIN=54V and the VOUT, FSW etc are at the default conditions of this demo board.

For the second question, we can also see LTC3886 instead of LTC3889 in the LTPowerPlay when running the demo board. I think it may be a bug but definitely it will not impact the demo board operation.