This document describes the power dissipation of the SOT-89 package. The value of power dissipation varies with the mount board conditions.
This document presents reference power‑dissipation data for the SOT‑89 package measured on a mounted board with natural convection, lead‑free soldering, and a 40 × 40 mm FR‑4 board where copper traces cover 50 % of the area. Two board configurations are described, one with a 1.6 mm thickness and another with a 0.8 mm ceramic board.
Data tables show power dissipation (mW) and thermal resistance (°C/W) versus ambient temperature for two maximum junction‑temperature limits: Tjmax = 125 °C and Tjmax = 150 °C. These curves can be used to evaluate the thermal performance of SOT‑89 devices in different operating environments.
| Package | SOT-89 |
|---|---|
| Maximum junction temperature (Tjmax) | 125 °C |
| Maximum junction temperature (Tjmax) | 150 °C |
The data were measured with the device mounted on a board, ambient natural convection, lead‑free soldering, board dimensions 40 × 40 mm, copper covering 50 % of the area, FR‑4 material, and 1.6 mm thickness.