ADP5360 Design problems


We want to design a wireless application and wanted to use the ADP5360 IC. We manufactured a few prototype PCBs and ran into a problem.

At first, when the PCB was connected to the battery, it caused the IC to overheat. Then, the PCB was connected to a voltage source, to simulate the battery. We found out that the current pulled out of the voltage source was roughly 500mA, without any load, so just the IC was pulling 500mA. We tried this with 3 different PCBs, the result was the same.

My question is: Is there something wrong with our schematic design (attached below)? We tried a simpler approach, we don't use Vout1, Vout2, because we regulate the voltage on another PCB. So we used Vsys as the voltage that is passed to the load. If the schematic is fine, I think maybe there was some error during manufacturing.

Thank you,

Florin Mazilu.

Parents Reply
  • Hello,

    We tried going without them, due to the very small form factor of our PCB, thinking that if we don't use Vout1 and Vout2 there won't be any problems. Do you think this could be the problem? 

    Also, when the input voltage Vbat is 4.2V, the current consumption is about 30mA, but if the voltage drops below 3.9V the current goes to 500mA. Also between 4.2V and 3.9V, the current increases slowly until 90mA. 

    Thank you,


  • 0
    •  Analog Employees 
    on Apr 27, 2021 10:53 AM in reply to Mazilu Florin


    ok, you don't use switcher 1 and 2. Why do you enable them via EN1 and EN2 pulled high?

    Have you checked what happens at Vout1 and Vout2 (without inductor, but switchers are enabled)?

    Have you tried a larger Resistor at ILIM to reduce current limit of 500mA?

    For testing the voltage source (>3.9V) should be connected towards VBUS, no battery attached at VISOB, no load attached to VSYS. What happens then?

    If VBUS is lowered below 3,9VV the ADP5360 should isolate VSYS from input.