MIC5388-MMYCS datasheet(9/12 Pages) MICREL

9 / 12 page

Micrel, Inc.

MIC5388/9

July 2011

M9999-071211-A

Substituting PD for PD(max) and solving for the ambient

operating temperature will give the maximum operating

conditions for the regulator circuit. The junction-to-

ambient thermal resistance for the minimum footprint is

108°C/W.

The maximum power dissipation must not be exceeded

for proper operation.

For example, when operating the MIC5388-MGYCS at

an input voltage of 3.6V and 150mA loads at each output

with a minimum footprint layout, the maximum ambient

operating temperature TA can be determined as follows:

0.39W = (125°C – TA)/(108°C/W)

TA = 82.88°C

Therefore, a 2.8V/1.8V application with 150mA at each

output current can accept an ambient operating

temperature of 82.88°C in a miniature 6-bump 0.5mm

pitch 1.5mm

× 1.0mm WLCSP package. For a full

discussion of heat sinking and thermal effects on voltage

regulators, refer to the “Regulator Thermals” section of

Micrel’s Designing with Low-Dropout Voltage Regulators

handbook. This information can be found on Micrel's

website at:

http://www.micrel.com/_PDF/other/LDOBk_ds.pdf

MIC5388-MMYCS Datasheet(PDF) 9 Page - Micrel Semiconductor