Datasheet

REG101
12
SBVS026D
FIGURE 7. Maximum Power Dissipation versus Ambient Temperature for the Various Packages.
POWER DISSIPATION
The REG101 is available in two different package configu-
rations. The ability to remove heat from the die is different
for each package type and, therefore, presents different
considerations in the printed circuit board (PCB) layout. The
PCB area around the device that is free of other components
moves the heat from the device to the ambient air. While it
is difficult to impossible to quantify all of the variables in a
thermal design of this type, performance data for several
configurations are shown in Figure 7.
Power dissipation depends on input voltage, load condition,
and duty cycle. Power dissipation is equal to the product of
the average output current times the voltage across the
output element, V
IN
to V
OUT
voltage drop.
Power dissipation can be minimized by using the lowest
possible input voltage necessary to assure the required
output voltage.
REGULATOR MOUNTING
Solder pad footprint recommendations for the various
REG101 devices are presented in the Application Bulletin
AB-132, “Solder Pad Recommendations for Surface-Mount
Devices” (SBFA015), available from the Texas Instruments
web site (www.ti.com).
1.2
1.0
0.8
0.6
0.4
0.3
0
Power Dissipation (W)
0 25 50 75 100 125
Ambient Temperature (°C)
CONDITIONS
SOT23-5
SO-8
PACKAGE
JA
SOT23-5 200°C/W
SO-8 150°C/W
θ
P=V –V I
D IN OUT OUT(AVG)
()
•