Datasheet LTC1735 (Analog Devices) - 8

LTC1735
U U U PI FU CTIO S VOSENSE:
Receives the feedback voltage from an external
INTVCC:
Output of the Internal 5.2V Regulator and EXTVCC resistive divider across the output. Switch. The driver and control circuits are powered from this voltage. Decouple to power ground with a 1µF ceramic
SENSE– :
The (–) Input to the Current Comparator. capacitor placed directly adjacent to the IC together with a
SENSE+:
The (+) Input to the Current Comparator. Built-in minimum of 4.7µF tantalum or other low ESR capacitor. offsets between SENSE– and SENSE+ pins in conjunction
V
with R
IN:
Main Supply Pin. Must be closely decoupled to power SENSE set the current trip threshold. ground.
PGOOD (LTC1735F Only):
Open-Drain Logic Output.
SW:
Switch Node Connection to Inductor and Bootstrap PGOOD is pulled to ground when the voltage on the Capacitor. Voltage swing at this pin is from a Schottky VOSENSE pin is not within ±7.5% of its set point. diode (external) voltage drop below ground to VIN.
EXTVCC:
Input to the Internal Switch Connected to INTVCC.
BOOST:
Supply to Topside Floating Driver. The bootstrap This switch closes and supplies VCC power whenever capacitor is returned to this pin. Voltage swing at this pin EXTVCC is higher than 4.7V. See EXTVCC connection in the is from a diode drop below INTV Applications Information section. Do not exceed 7V on CC to (VIN + INTVCC). this pin and ensure EXTVCC ≤ VIN.
TG:
High Current Gate Drive for Top N-Channel MOSFET. This is the output of a floating driver with a voltage swing
PGND:
Driver Power Ground. Connects to the source of equal to INTV bottom N-channel MOSFET, the anode of the Schottky CC superimposed on the switch node voltage SW. diode, and the (–) terminal of CIN.
BG:
High Current Gate Drive for Bottom N-Channel MOSFET. Voltage swing at this pin is from ground to INTVCC. 1735fc 8