SBVS318B July 2017 – January 2019 TPS7A92
PRODUCTION DATA.
The JEDEC standard now recommends the use of psi (Ψ) thermal metrics to estimate the junction temperatures of the LDO when in-circuit on a typical PCB board application. These metrics are not strictly speaking thermal resistances, but rather offer practical and relative means of estimating junction temperatures. These psi metrics are determined to be significantly independent of the copper-spreading area. The key thermal metrics (ΨJT and ΨJB) are given in the Thermal Information table and are used in accordance with Equation 8.
where
For a more detailed discussion on thermal metrics and how to use them, see the Semiconductor and IC Package Thermal Metrics application report.