This part is a kind of semiconductor called MD1803DFH.

Function of this product has High voltage NPN Power transistor.

Manufacturers : ST Microelectronics

Image and pinout :

Some of the text within the PDF file :

MD1803DFH High voltage NPN Power transistor for standard definition CRT display Features ■ ■ ■ ■ ■ ■ ■ ■ State-of-the-art technology: – Diffused collector “enhanced generation” More stable performance versus operating temperature variation Low base drive requirement Tighter hFE range at operating collector current Fully insulated power package u.l. compliant Creepage distance path > 4mm Integrated free wheeling diode In compliance with the 2002/93/ec european directive TO-220FH 1 2 3 Applications ■ Internal schematic diagram Horizontal deflection output for TV Description The MD1803DFH is manufactured using Diffused Collector in Planar Technology adopting new and enhanced high voltage structure. The new MD product series show improved silic [ ... ]

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