mic47100 Micrel Semiconductor, mic47100 Datasheet - Page 11

• Manufacturer Part Number: mic47100
• Description: Mic47100 1a High Speed Low Vin Ldo
• Manufacturer: Micrel Semiconductor

Micrel, Inc.
To determine the maximum ambient operating
temperature of the package, use the junction-to-
ambient thermal resistance of the device and the
following basic equation:
T
the die θ
The table below shows junction-to-ambient thermal
resistance for the MIC47100 in the MLF
Substituting P
operating
operating conditions for the regulator circuit. The
junction-to-ambient
minimum footprint is 90°C/W.
8-pin 2mm x 2mm
February 2008
J(max)
Package
= 125°C, the maximum junction temperature of
MLF
JA
thermal resistance = 90°C/W.
®
temperature
D
for P
P
Thermal Resistance
D(MAX)
D(max)
thermal
Recommended
=
Minimum
Footprint
90°C/W
and solving for the ambient
will
⎝
⎛
θ
JA
T
J(MAX)
give
resistance
JA
- T
the
®
A
package.
maximum
for
2°C/W
θ
JC
the
11
The maximum power dissipation must not be
exceeded for proper operation.
For example, when operating the MIC47100-1.2YML
at an input voltage of 1.8V and a 1A load with a
minimum footprint layout, the maximum ambient
operating temperature T
follows:
Therefore, a 1.2V application with 1A of output current
can accept an ambient operating temperature of 71°C
in a 2mm x 2mm MLF
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
T
0
6 .
A
W
=
71
=
°
(
C
125
(
90
°
°
C
C
/
−
W
T
A
)
)
®
package. For a full discussion
A
can be determined as
M9999-022108-A
[phone]
MIC47100