This part is a kind of semiconductor called B3965D.

Function of this product has N- and P-Channel 40-V (D-S) MOSFET.

Manufacturers : BiTEK

Image and pinout :

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B3965D N- and P-Channel 40-V (D-S) MOSFET General Description The B3965D is the N- and P-Channel logic enhancement mode power field effect transistors are produced using high cell density, DMOS trench technology. This high density process is especially tailored to minimize on-state resistance. These devices are particularly suited for low voltage application such as cellular phone and notebook computer power management and other battery powered circuits with high-side switching, and low in-line power loss are needed in a very small outline surface mount package. Pin Configuration Features 40V/5.2A, RDS(ON)=40mΩ@VGS=10V (N-Ch) 40V/4.9A, RDS(ON)=45mΩ@VGS=4.5V (N-Ch) -40V/-4.5A, RDS(ON)=54mΩ@VGS=-10V (P-Ch) -40V/-3.9A, RDS(ON)=72mΩ@VGS=-4.5V (P-Ch) Super High Density Cell Design For [ ... ]

B3965D PDF Datasheet Download