PNP switching and amplification — 500 mA, 45 V, SOT-23
The BC807-40E6359: This is a PNP general-purpose transistor rated for a continuous collector current of 500 mA and a collector-emitter breakdown voltage of 45 V — suitable for medium-current switching and linear amplification in low-voltage circuits. The 330 mW power dissipation at 25°C ambient defines the thermal budget: in a typical SOT-23 layout on standard FR-4, the junction stays within the 150°C maximum rating for loads up to about 200 mA continuous, depending on ambient temperature and copper area.
Saturation voltage and switching speed
Vce(sat) is specified at 700 mV maximum with a base current of 50 mA and collector current of 500 mA — this low saturation voltage minimizes conduction loss in the on-state for switching applications. The 200 MHz transition frequency (fT) indicates the transistor can amplify signals up to that frequency; for switching applications, practical switching times are in the tens of nanoseconds, making it suitable for PWM control up to several hundred kilohertz.
Housed in the industry-standard SOT-23-3 package (also designated TO-236-3, SC-59, and PG-SOT23 by Infineon), the BC807-40E6359 fits the common three-lead footprint used across thousands of designs — no board layout change needed when substituting between SOT-23 PNP transistors from different manufacturers. The surface-mount package is compatible with reflow soldering and automated pick-and-place assembly, supporting high-volume production.