LTC4447

6

4447f

BLOCK DIAGRAM

PIN FUNCTIONS

NC (Pins 1, 2): No Connection Required.

TG (Pin 3): High Side Gate Driver Output (Top Gate). This

pin swings between TS and BOOST.

TS (Pin 4): High Side MOSFET Source Connection (Top

Source).

BG (Pin 5): Low Side Gate Driver Output (Bottom Gate).

GND (Pin 6): Chip Ground.

IN (Pin 7): Input Signal. Input referenced to an internal

this pin is floating, an internal resistive divider triggers a

shutdown mode in which both BG (Pin 5) and TG (Pin 3)

are pulled low. Trace capacitance on this pin should be

minimized to keep the shutdown time low.

buffer and logic. Connect this pin to the power supply

of the controller that is driving IN (Pin 7) to match input

low side gate driver output directly and the high side gate

driver output through an internal Schottky diode con-

nected between this pin and BOOST. A low ESR ceramic

bypass capacitor should be tied between this pin and

GND (Pin 6).

BOOST (Pins 10, 11, 12): High Side Bootstrapped Supply.

An external capacitor should be tied between these pins

and TS (Pin 4). An internal Schottky diode is connected

forward voltage drop of the Schottky diode.

Exposed Pad (Pin 13): Ground. The exposed pad must be

soldered to PCB ground for optimal electrical and thermal

performance.

10

3

4

SHOOT-

THROUGH

PROTECTION

THREE-STATE

INPUT

BUFFER

LEVEL

SHIFTER

INTERNAL

SUPPLY

UNDERVOLTAGE

LOCKOUT

UNDERVOLTAGE

LOCKOUT

BOOST

11

12

TG

TS

5

8

BG

4447 BD

7k

7k

9

7

IN

6

GND

13 GND