Datasheet

LM21305
SNVS639F –DECEMBER 2009–REVISED MARCH 2013 www.ti.com
I
OUT
= Output (load) current
R
dcr
= Inductor parasitic DC resistance
It is important to always keep the LM21305 operating junction temperature (T
J
) below 125°C to assure reliable
operation. If the junction temperature exceeds 160°C, the device will cycle in and out of thermal shutdown. If
thermal shutdown occurs, it is a sign of inadequate heat-sinking and/or excessive power dissipation in the
device. PC board heat-sinking can be improved by using more thermal vias, a larger board, or more heat-
spreading layers within that board.
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