Datasheet

1
2
3
4
16151413
12
11
10
9
7 6 5
L1
CIN
R1R2
COUT
VOUT
GND
GND
AVIN
8
EN
PG
to
AGND
PVIN
to GND
plane
C
TPS62140, TPS62140A
TPS62141, TPS62142, TPS62143
www.ti.com SLVSAJ0B –NOVEMBER 2011–REVISED JUNE 2013
Figure 41. Layout Example
THERMAL INFORMATION
Implementation of integrated circuits in low-profile and fine-pitch surface-mount packages typically requires
special attention to power dissipation. Many system-dependent issues such as thermal coupling, airflow, added
heat sinks and convection surfaces, and the presence of other heat-generating components affect the power-
dissipation limits of a given component.
Three basic approaches for enhancing thermal performance are listed below:
• Improving the power dissipation capability of the PCB design
• Improving the thermal coupling of the component to the PCB by soldering the exposed thermal pad
• Introducing airflow in the system
For more details on how to use the thermal parameters, see the application notes: Thermal Characteristics
Application Note (SZZA017), and (SPRA953).
The TPS6214X is designed for a maximum operating junction temperature (T
J
) of 125°C. Therefore, the
maximum output power is limited by the power losses that can be dissipated over the actual thermal resistance,
given by the package and the surrounding PCB structures. If the thermal resistance of the package is given, the
size of the surrounding copper area and a proper thermal connection of the IC can reduce the thermal
resistance. To get improved thermal behavior, it is recommended to use top layer metal to connect the device
with wide and thick metal lines. Internal ground layers can connect to vias directly under the IC for improved
thermal performance.
If short-circuit or overload conditions are present, the device is protected by limiting internal power dissipation.
Experimental data, taken from the TPS62140 EVM, shows the maximum ambient temperature (without additional
cooling like airflow or heat sink), that can be allowed to limit the junction temperature to at most 125°C (see
Figure 37).
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Product Folder Links: TPS62140 TPS62140A TPS62141 TPS62142 TPS62143