ADP7142(ARDZ-5.0-R7) output out of range, fixed in -0.786v

Hi all, I hope you can help me with the following:

 

I'm testing a dual power supply with the adp7142 for +10v (positive 200mA) and the tps7a30 for -10v (negative 200mA). The source is a pair of 12v batteries in series configuration so the adp7142 is applied with +12v on its input and the tps7a30 is applied with -12v. When both regulators are started through a common switch (nearly at the same time) the output voltages are within range -10.02v and +9.99v respectively. The problem arises when only the positive input is disconnected and then connected back, after this the output of the adp7142 is -0.786v and the sense/adj pin is -0.401v. Also repetitive disconnections and connections won’t fix the problem, the adp7142 output stays at -0.786v. Only by restarting both regulators through the common switch returns the output voltages to the correct values  

 

Here is the schematic for the adp7142:

 

 

Thank you very much

David

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    •  Analog Employees 
    on Aug 2, 2018 4:02 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

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    EZ Admin
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  • 0
    •  Analog Employees 
    on Aug 2, 2018 4:02 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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