LTC3522 datasheet(7/20 Pages) LINER

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LTC3522

3522f

SW1B (Pin 10): Buck-Boost Switch Node That Must be

Connected to One Side of the Buck-Boost Inductor.

SW1A (Pin 11): Buck-Boost Switch Node That Must be

Connected to One Side of the Buck-Boost Inductor.

VOUT1 (Pin 12): Buck-Boost Output Voltage Node. This pin

should be connected to a low ESR output capacitor. The

capacitor should be placed as close to the IC as possible

and should have a short return to ground.

PGND1 (Pin 13): High Current Ground Connection for

Buck-Boost Switch B and the Buck Converter Synchronous

Rectiﬁer. The PCB trace connecting this pin to ground

should be made as short and wide as possible.

SW2 (Pin 14): Buck Converter Switch Node That Must be

Connected to the Buck Inductor.

PVIN2 (Pin 15): High Current Power Supply Connection

Used to Supply the Buck Converter Power Switch. In ad-

dition this pin is the supply pin for the internal circuitry of

the LTC3522. This pin should be bypassed by a 4.7μF or

larger ceramic capacitor. The bypass capacitor should be

placed as close to the pin as possible and should have a

short return path to ground. Pins PVIN1 and PVIN2 must

be connected together in the application circuit.

SHDN2 (Pin 16): Buck Active-Low Shutdown Pin. Forcing

this pin above 1.4V enables the buck converter. Forcing

this pin below 0.4V disables the buck converter. This pin

cannot be left ﬂoating.

Exposed Pad (Pin 17): The Exposed Pad must be electri-

cally connected to ground. Pins PGND1, PGND2, GND,

and the Exposed Pad must be connected together in the

application circuit.

PIN FUNCTIONS

LTC3522 Datasheet(PDF) 7 Page - Linear Technology