Datasheet for the SG3526 in a 173 KB PDF, with rev2f in the name indicating document revision 2F. The SG3526 belongs to the classic SG35xx family of PWM controllers used in switch-mode power supplies, inverters and converters. Technicians consult it for pin functions, oscillator timing components, soft-start, current limiting and dual output drive when a supply will not start. Check the reference voltage pin and oscillator first during diagnosis, and confirm the marking matches this part.
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