LTC3734_15 Datasheet, PDF (8/28 Pages) Linear Technology – Single-Phase, High Efficiency DC/DC Controller for Intel Mobile CPUs

LTC3734
PIN FUNCTIONS
SW (Pin 23): Switch Node Connection to Inductor. Volt-
age swing at this pin is from a Schottky diode (external)
voltage drop below ground to V_IN.
TG (Pin 24): High Current Gate Drive for Top N-Channel
MOSFETs. This is the output of a floating driver with a
voltage swing equal to PV_CC superimposed on the switch
node voltage SW.
BOOST (Pin 25): Bootstrapped Supply to the Topside
Floating Driver. External capacitor is connected between the
BOOST and SW pins, and a Schottky diode is connected
between the BOOST and PV_CC pins.
PGOOD (Pin 26): Power Good Indicator Output. This pin
is open drain when output is within ±10% of its set point.
When output is not within the ±10% window, this pin is
pulled to ground. An internal timer watches over VID, state
transitions, overvoltage or undervoltage conditions, then
masks PGOOD from going low for 110µs.
MCH_PG (Pin 27): MCH Power Good Input. Output voltage
remains VBOOT for 15 clock cycles after the assertion of
MCH_PG. This delay is only sensitive to the rising edge
of the MCH_PG logic signal.
V_FB (Pin 28): Input to the error amplifier that compares
the feedback voltage to the internal 0.6V reference voltage.
SV_CC (Pin 29): Signal Power Pin. The internal control
circuits are powered from this voltage source.
DPRSLPVR (Pin 30): Deeper Sleep State Input. When
the signal to this pin is high, the voltage regulator enters
deeper sleep state and its output is determined by the
parallel resistor value of RDPRSLP and RDPSLP. When the
signal is low, the voltage regulator exits deeper sleep state.
FREQSET (Pin 31): Frequency Set Pin. Apply a DC volt-
age between 0V and 5V to set the operating frequency
of the internal oscillator. This frequency is the switching
frequency of the controller.
PSIB (Pin 32): Power Status Indicator Input. When the
signal to this pin is high, the controller operates in fully
synchronous switching mode for fastest transient and
lowest ripple. When the signal is low, controller enters
power saving mode, providing high efficiency at light load.
SGND (Exposed Pad Pin 33): Signal Ground. Must be
soldered to the PCB.
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