Level Shift Current Consumption

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ricks@campbells...
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Level Shift Current Consumption

When this device is used to shift voltage levels between 3.3V and 5V, what is the quiescent (static) current consumption?
There is a comment in App note an-1104 that says: "The enable pin turns off internal oscillator to save power when level shifting is not needed." This seems to imply there is an oscillator as part of the level shift circuitry.

Thanks

Device: 
Device Number: 
SLG46538
PavloZ
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Thanks for your question. 

Thanks for your question. 

Yes, there is an oscillator used for few delay blocks and it is Forced On to make quick responce when data transfer starts. The current consumption at that mode is near 200uA.

Thanks to you we've found some inacuracy in the app note, there is an opporunity to connect Enable pin with to OSC's Power Down. In that case quiescent current can be reduced to less 1uA.

ricks@campbells...
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If delays are not needed,

If delays are not needed, then there is no need for the oscillator, right? Can voltage level conversion (3V to 5V) still be done without the oscillator? Will current consumption (static) be around 1 uA?

Thanks!

luke.thomas
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Hi Rick,

Hi Rick,

The delays are needed for the AN1104 design because the lines will lockup without them.

luke.thomas
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Hi Rick,

Hi Rick,

Thanks for bringing this up. Additionally, you can use alternative ways to level shift as shown in my attachment. The Quiescent current when EN = 0 is 480nA , and 78µA when EN=1 for the a GPAK implementation in the SLG46855.