LTC3026 - Best Way to Sequence ON and OFF

The best way to sequence the LTC3026 on is SHDN = low then IN = high then BST = high then SHDN=high.  The best way to turn off the LTC3026 is the opposite order.  I tried this in the lab with the demonstration circuit at no load and I show the method works with the scope capture image below.  I also show an image of the schematic.

Conditions:  LT3026EDD DC833A 2.5VIN 5VBST 1.8VOUT at no load,VCIN VSHDN VBST VCOUT startup_0-sequence.bmp

The best way to sequence the LTC3026 on is SHDN = low then IN = high then BST = high then SHDN=high.  The best way to turn off the LTC3026 is the opposite order.  I tried this in the lab with the demonstration circuit at no load and I show the method works with the scope capture image below.  I also show an image of the schematic.

Conditions:  LT3026EDD DC833A 2.5VIN 5VBST 1.8VOUT at no load,VCIN VSHDN VBST VCOUT startup_0-sequence.bmp

Hi ARad, 

Thanks for this! in the case of incorrect sequencing, specifically applying BST = high before IN = high, are there any negative effects? i.e is there any chance the device could self power before IN=high, or could the part be potentially damaged? 

BR

Dan

I looked at my history and the field reported BST can "leak" to OUT if the correct startup sequence is not followed.  No one reported failures due to startup sequencing.  The image below shows an error in the demo board design that I will fix at the first opportunity.   The datasheet has been corrected for that issue already.