MIC5330 Datasheet, PDF (9/10 Pages) Micrel Semiconductor – Dual, 300mA UCap LDO in 2mm x 2mm MLF

Micrel, Inc.
Package
8-Pin 2x2 MLF^®
θ_JA Recommended
Minimum Footprint
90°C/W
Thermal Resistance
Substituting P_D for P_D(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 90°C/W.
The maximum power dissipation must not be
exceeded for proper operation.
For example, when operating the MIC5330-MFYML at
MIC5330
an input voltage of 3.3V and 300mA loads at each
output with a minimum footprint layout, the maximum
ambient operating temperature T_A can be determined
as follows:
0.99W = (125°C – T_A)/(90°C/W)
T_A=62.9°C
Therefore, a 2.8V/1.5V application with 300mA at
each output current can accept an ambient operating
temperature of 62.9°C in a 2mm x 2mm MLF^®
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
August 2006
9
M9999-080306