Good morning, I tell you a little about this team. As the title says I arrive at the workshop completely inoperative, dead as they say. I take it apart and find the typical problem of this equipment, which is the damage on the main board of the smd D4 diode, it is a Schottky Diode SS34B of 3A and 40V, which is connected to the output of U1 which is the EUP3490, being short the diode, the U1 does not deliver the 5V for the standby. I also discover that the U1 was damaged, I proceed to change both for exactly the same, and after changing them the equipment remains without standby, in the 5V line I have only a fluctuating voltage between 3.4V and 3.7V. I thought about the source, but I tried it separately with load and it worked perfectly, the source delivers a single voltage of 35V. The EUP3490 has a wide operating range according to the input voltage ranging from 4.75V to 40V. I try to inject the integrated voltage from my laboratory source and gradually increased the input voltage and the 5V appeared at the output, and here comes the question, when I inject a voltage value within the range only the fluctuating voltage appears at the exit, but if the injection gradually appear 5V and remain stable, I hope to explain myself well, I would like some suggestion that it may be happening. From already thank you very much.

According to EUP3490 data, Resistors R22, R23, R27 and R28 are important for their operation Did you check them?

Hi. I have the same team and the same thing happened to me. I would like to know if where I could get the components from Ya thanks