LP78071 datasheet(13/16 Pages) POWER

13 / 16 page

Preliminary Datasheet

LP78071

LP78071 – 00 Version 1.0 Feb.-2014

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Example: Consider the extreme case when an LP78071 is

operating from a 6V supply providing 250mA to a 3V Li-Ion

battery, the switching regulator and the LDO are off. The

ambient temperature above which the LP78071 will begin to

reduce the 250mA charge current is approximately:

(Correctly soldered to a 2500mm2 double-sided 1 oz.

copper board, the LP78071 has a thermal resistance of

approximately 43°C/W.)

T =

If there is more power dissipation due to the switching

regulator or the LDO, the thermal regulation will kick in at a

somewhat lower temperature than this. In the above

circumstances, the LP78071 can be used above 82.75°C, but

the charge current will be reduced from 250mA. The

approximate current at a given ambient temperature can be

calculated:

Note: 1V = 1J/C = 1W/A

Furthermore, the voltage at the ISET pin will change

proportionally with the charge current as discussed in the

ISET ramming Charge Current section.

LP78071 Datasheet(PDF) 13 Page - Lowpower Semiconductor inc