LTC3789 pin FuncTions (SSOP/QFN)INTVCC (Pin 21/Pin 18): Output of the Internal Linear Low to (VIN + INTVCC). Voltage swing at the BOOST2 pin is Dropout Regulator. The driver and control circuits are from INTVCC to (VOUT + INTVCC). powered from this voltage source. Must be bypassed to power ground with a minimum of 4.7µF tantalum, ceramic, TG1, TG2 (Pins 26, 17/Pins 23, 14): High Current or other low ESR capacitor. Gate Drives for Top N-Channel MOSFETs. These are the outputs of floating drivers with a voltage swing equal VIN (Pin 22/Pin 19): Main Supply Pin. A bypass capacitor to INTVCC – 0.5V superimposed on the switch node should be tied between this pin and the power ground pin. voltage SW. BG1, BG2 (Pins 23, 19/Pins 20, 16): High Current SW1, SW2 (Pins 27, 16/Pins 24, 13): Switch Node Gate Drives for Bottom (Synchronous) N-Channel Connections to Inductors. Voltage swing at the SW1 MOSFETs. Voltage swing at these pins is from ground to pin is from a Schottky diode (external) voltage drop INTVCC. below ground to VIN. Voltage swing at the SW2 pin is PGND (Pin 24/Pin 21): Driver Power Ground. Connects from a Schottky diode voltage drop below ground to to COUT and RSENSE (–) terminal(s) of CIN. VOUT. BOOST1, BOOST2 (Pins 25, 18/Pins 22, 15): Bootstrapped PGOOD (Pin 28/Pin 25): Open-Drain Logic Output. Supplies to the Top Side Floating Drivers. Capacitors PGOOD is pulled to ground when the voltage on the VFB are connected between the BOOST and SW pins and pin is not within ±10% of its regulation window, after the Schottky diodes are tied between the BOOST and INTVCC internal 20µs power-bad mask timer expires. pins. Voltage swing at the BOOST1 pin is from INTVCC 3789fc 10 For more information www.linear.com/LTC3789 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration order information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Typical Application Related Parts