Datasheet LTC3522 (Analog Devices) - 7

LTC3522
PIN FUNCTIONS SW1B (Pin 10):
Buck-Boost Switch Node That Must be
PVIN2 (Pin 15):
High Current Power Supply Connection Connected to One Side of the Buck-Boost Inductor. Used to Supply the Buck Converter Power Switch. In ad- dition this pin is the supply pin for the internal circuitry of
SW1A (Pin 11):
Buck-Boost Switch Node That Must be the LTC3522. This pin should be bypassed by a 4.7μF or Connected to One Side of the Buck-Boost Inductor. larger ceramic capacitor. The bypass capacitor should be
VOUT1 (Pin 12):
Buck-Boost Output Voltage Node. This pin placed as close to the pin as possible and should have a should be connected to a low ESR output capacitor. The short return path to ground.
Pins PVIN1 and PVIN2 must
capacitor should be placed as close to the IC as possible
be connected together in the application circuit.
and should have a short return to ground.
SHDN2 (Pin 16):
Buck Active-Low Shutdown Pin. Forcing
PGND1 (Pin 13):
High Current Ground Connection for this pin above 1.4V enables the buck converter. Forcing Buck-Boost Switch B and the Buck Converter Synchronous this pin below 0.4V disables the buck converter. This pin Rectifi er. The PCB trace connecting this pin to ground cannot be left fl oating. should be made as short and wide as possible.
Exposed Pad (Pin 17): The Exposed Pad must be electri- SW2 (Pin 14):
Buck Converter Switch Node That Must be
cally connected to ground. Pins PGND1, PGND2, GND,
Connected to the Buck Inductor.
and the Exposed Pad must be connected together in the application circuit.
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