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VIN

21

LM60440, LM60430

www.ti.com

SNVSBN5A – FEBRUARY 2020 – REVISED JUNE 2020

Product Folder Links: LM60440 LM60430

Submit Documentation Feedback

Copyright © 2020, Texas Instruments Incorporated

Figure 10. Setup for External UVLO Application

where

•

•

(9)

9.2.2.11 Maximum Ambient Temperature

As with any power conversion device, the LM604x0 dissipates internal power while operating. The effect of this

power dissipation is to raise the internal temperature of the converter above ambient. The internal die

limited to 150°C. This establishes a limit on the maximum device power dissipation and therefore the load

current. Equation 10 shows the relationships between the important parameters. It is easy to see that larger

efficiency can be estimated by using the curves provided in this data sheet. If the desired operating conditions

cannot be found in one of the curves, then interpolation can be used to estimate the efficiency. Alternatively, the

EVM can be adjusted to match the desired application requirements and the efficiency can be measured directly.

purposes and must not be used to estimate the thermal performance of the application. The values reported in

that table were measured under a specific set of conditions that are rarely obtained in an actual application.

where

•

η = efficiency

(10)

temperature/flow, PCB area, copper heat-sink area, number of thermal vias under the package, and adjacent

component placement, just to mention just a few. The copper area given in the graph is for each layer; the top

and bottom layers are 2 oz. copper each, while the inner layers are 1 oz. It must be remembered that the data

given in these graphs are for illustration purposes only, and the actual performance in any given application

depends on all of the previously mentioned factors.