This part is a kind of semiconductor called U209B3.

Function of this product has Phase Control Circuit - Tacho Applications.

Manufacturers : TEMIC Semiconductors

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TELEFUNKEN Semiconductors U209B3/ U209B3–FP Phase Control Circuit – Tacho Applications Description: The integrated circuit U209B3, is designed as a phase control circuit in bipolar technology. It has also protection circuit for the supply. Due to integration of many functions, it leads to significant cost and space saving as well as increased reliability. At the same time, it gives the designer free hand to select varieties of regulators to choose from and switching characteristics according to its choice. Features D Internal frequency to voltage converter D Externally controlled integrated amplifier D Automatic soft start with minimised ”dead time” D Voltage and current synchronisation D Retriggering D Triggering pulse typ. 155 mA D Internal supply voltage monitoring D Temperat [ ... ]

U209B3 PDF Datasheet Download