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OPA211 , OPA2211, OPA2111 / power on sequence of Positive Power Supply and Negative Power Supply

Ryuji
Guru 20090 points
Other Parts Discussed in Thread: OPA211
Hello,
 
Could you please let me know the power on sequece of V+/V- power supply for OPA211, OPA2211 and OPA2111?
 
My customer use these device by +/-10V ~ +/-15V.
And in thier system, negative supply is turned on at first.
 
Are there any restriction of power on sequence of V+ / V-?
 
for example,,,
  At the Same time ?
  No restriction?
  No restriction within 30ms ? etc.
 
Best Regards,
Ryuji Asaka     
  • 0
    TI__Expert 6275 points

    See attached for considerations of Op AMps with dual supplies and sytem recommendations for asymmetrical power-up and power-down of supplies.

    Op Amp Power Sequence.ppt
  • 0 in reply to Tim Green1
    Guru 20090 points
    Hello Tim san,
     
    Thank you for the information.
    I understood that , asymmetrical power-up and power-down is recommended.
    And in your attached file, Iq is through to reverse biased input stage.
    So, If  "V-"  is powered on at first, V+ is biased to negative voltage and device has overstress.
     
    (1)
    Is this overstress occured  in all OpAmps ?
    I think that absolute maximum rating is diffrence in opamps.
    If no, please let me know the OPAx211 cases.
     
    OPAx211's absolute rating is as below.
    Supply Voltage : VS = (V+) – (V–)  = 40V
    Input Voltage  : (V–) – 0.5 to (V+) + 0.5 V
    I think that we can use V-=-15V and V+=0V in this absolute rating.
     
    (2)
    In my customer's case, V- is powered on at first by -10V~-15V .
    So, we can avoid overstress possibility if we add Z2 ?
    Z2 is Zeners between V+ and GND in your attached file's Page 3.
     
     
    Best Regards,
    Ryuji Asaka
  • 0 in reply to Ryuji
    Guru 20090 points
    Hello Tim san,
     
    Sorry for bothering you.
    But could I have the comment please ?
     
    Best Regards,
    Ryuji Asaka