LTC3553 floating STBY

Hi All,

I've made a batch of devices using LTC3553 as a power controller (pushbutton, LDO and LiPo charger are used). Some time ago I suddenly found out that due to a mistake when tracing the STBY pin of the LTC3553 left floating. This is forbidden by the datasheet, but it is not explained why.
I understand that this must b fixed, but most of the batch has already found it's way to customers and it's impossible to repair.
What are the expected (or unexpected) consequences could have a floating STBY pin?
Thanks in advance for any hint!



  • +1
    •  Analog Employees 
    on Aug 15, 2019 6:29 PM


    This is a high impedance input pin. If this pin was to float the voltage level could rise above or fall below the STBY trip point and change states of the IC in or out of standby. There is no way to assure what state the part will be in with the STBY pin floating.