This part is a kind of semiconductor called OB2226.

Function of this product has High Precision Low Cost MCM Power Switch.

Manufacturers : On-Bright Electronics

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On-bright Confidential to OB2226 High Precision Low Cost MCM Power Switch GENERAL DESCRIPTION OB2226 is a high performance, high precision and low cost PWM Power switch for non-isolated buck application. It combines a dedicated current mode PWM controller (with a high voltage power MOSFET with DIP7 package) and built-in error amplifier for low cost and component count. With precise inner resistor divider, precise reference of EA and load compensation, accurate constant voltage regulation at universal AC input can be guaranteed. For high efficiency, oscillator with frequency-reduction control is implemented. And EMI performance is achieved with On-Bright proprietary frequency shuffling technique. OB2226 offers power on soft start control and protection coverage with auto-recovery features [ ... ]

OB2226 PDF Datasheet Download