design spec of LDO regulator?

[chenmy]

Dear All:

A simple question about LDO:what do you think should be the design spec for the LDO's current load?max value or the average value?

(I wish to use an LDO for digital power supply(1.0V).In the normal working condition, the max current value for digital power supply is about 2mA ,while the average current value is about 0.5mA.the spec should be 2mA or 0.5mA?)

Thx very much!
chenmy

 

[gevy]

If current spikes do max value that design spec must have average value.
Besides, LDO output must have capacitor for deleting spikes.

 

[safwatonline]

in DC and AC u work on average current (with margin) while in transient u work on average loaded by spikes

 

[sudheer_vlsi]

i think its average curre.t

 

[jianbinma1979]

i agree with safwatonline

 

[jonneylu]

both of max and average is needed

 

[leo_o2]

I think you can design current limit>1.5XMax current.
For general performance simulation, you can use average current loading.

 

[elantra]

of course max load. your design should cover all the load range, so the spec should be at least the upper load.