FAN49100 TinyPower Buck-Boost Regulator onsemi / Fairchild FAN49100 TinyPower Buck-Boost Regulator is a high-efficiency buck-boost switching mode regulator which accepts input voltages either above or below the regulated output voltage. The FAN49100 can deliver up to 2A while regulating the output at 3.3V and uses full-bridge architecture with synchronous rectification. The onsemi / Fairchild FAN49100 exhibits seamless transition between step-up and step-down modes reducing output disturbances.