ST1S12 quiescent current is too high

[Central SUPPORT]

We are using an ST1S12GR device and the input current is >2.5mA even with only the feedback loop connected and ENable pin connected to Vin. Feedback resistors values are 220k resp. 59k. According to Datasheet Table 8 (“Electrical Characteristics�?) Quiescent Current Iq should be max 650uA when non-switching, so how can we reduce current consumption?  

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[Central SUPPORT]

Since you have ENable pin connected to Vin your device is already switching even if you have not connected it to any load. Therefore input current cannot meet the value specified for non-switching state.

ENable pin is dedicated to switching ON and OFF for applications where Vin is connected to voltage source permanently. In this case you can decrease the current consumption if you pull the ENable pin down to the ground using pull-down resistor whenever you do not need the device to be operating. The device will start operating (switching) right when you drive the ENable pin to Vin.