LT3653 TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise notedVC CurrentVC Operating Range 15 2.0 CURRENT LIMIT CLAMP 10 1.8 1.6 5 1.4 0 1.2 –5 TAGE (V) 1.0 SWITCHING THRESHOLD –10 0.8 VC VOL VC PIN CURRENT (μA) 0.6 –15 0.4 –20 0.2 –25 0.0 4 4.4 4.8 5.2 5.6 6 -50 -25 0 25 50 75 100 125 VOUT (V) TEMPERATURE (ºC) 3653 G09 3653 G10 PIN FUNCTIONSVIN (Pin 1): The VIN pin supplies current to the LT3653’s ISENSE (Pin 6): The ISENSE pin is the positive input to the internal regulator and the internal power switch. Locally internal current sense resistor of the output current limit bypass this pin with a capacitor. circuit. The ISENSE pin is also the anode of the internal BOOST diode. HVOK (Pin 2): The HVOK pin is a status pin which indi- cates that the internal bias rail is present and that an input BOOST (Pin 7): The BOOST pin provides a drive voltage, undervoltage lockout fault, an overvoltage lockout fault or higher than the input voltage, to the internal power switch. an over temperature fault are not present. The BOOST pin is internally connected to the cathode of the BOOST diode. VC (Pin 3): The VC pin is the output of the internal error amplifi er and is internally compensated. The voltage on this SW (Pin 8): The SW pin is the output of the internal power pin controls the peak switch current. Connect this pin to switch. Connect this pin to the inductor, catch diode and the battery charger VC pin for battery tracking function. boost capacitor. ILIM (Pin 4): Connect a resistor to GND to program the Exposed Pad (Pin 9): Ground. The Exposed Pad must be output current limit of the regulator. See the ILIM Resistor soldered to the PCB and electrically connected to ground. section in Application Information. Use a large ground plane and vias to optimize thermal performance. VOUT (Pin 5): The VOUT pin is connected to the negative terminal of the internal current sense resistor of the output current limit circuit. Maximum VOUT voltage is regulated to 4.8V. 3653f 5