LTC3542_15 Datasheet, PDF (6/16 Pages) Linear Technology – 500mA, 2.25MHz Synchronous Step-Down DC/DC Converter

LTC3542
PIN FUNCTIONS (DFN/TSOT-23)
V_FB (Pin 1/Pin 3): Output Feedback Pin. Receives the
feedback voltage from an external resistive divider across
the output. Nominal voltage for this pin is 0.6V.
V_IN (Pin 2/Pin 1): Power Supply Pin. Must be closely
decoupled to GND.
GND (Pin 3/Pin 2): Ground Pin.
SW (Pin 4/Pin 6): Switch Node Connection to Inductor.
This pin connects to the drains of the internal main and
synchronous power MOSFET switches.
MODE/SYNC (Pin 5/Pin 5): Mode Selection and Oscillator
Synchronization Pin. This pin controls the operation of the
device. When tied to GND or V_IN, Burst Mode operation or
pulse skipping mode is selected, respectively. Do not float
this pin. The oscillation frequency can be synchronized to
an external oscillator applied to this pin and pulse skipping
mode is automatically selected.
RUN (Pin 6/Pin 4): Converter Enable Pin. Forcing this pin
above 1.5V enables this part, while forcing it below 0.3V
causes the device to shut down. In shutdown, all functions
are disabled drawing <1μA supply current. This pin must
be driven; do not float.
GND (Pin 7, DFN Package Only): Exposed Pad. The Ex-
posed Pad is ground. It must be soldered to PCB ground
to provide both electrical contact and optimum thermal
performance.
BLOCK DIAGRAM
V_FB
0.6V
–
EA
+
MODE/SYNC
V_IN
SLOPE COMPENSATION
OSC
–
+
V_B
+
BURST
LOGIC
MODE
DETECT
MODE
CLKIN
RUN
SHUTDOWN
0.6V REF
I_COMP
ANTI-
SHOOT
THROUGH
I_RCMP
V_IN
SW
GND
3542 BD
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