LTC3522_15 Datasheet, PDF (7/20 Pages) Linear Technology – Synchronous 400mA Buck-Boost and 200mA Buck Converters

LTC3522
PIN FUNCTIONS
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.
V_OUT1 (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.
PV_IN2 (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 PV_IN1 and PV_IN2 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.
3522fa
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