LTC3405A-1.375 WUTYPICAL PERFOR A CE CHARACTERISTICS TA = 25 ° C unless otherwise noted.(From Figure 1a)Load StepLoad StepLoad Step V V OUT OUT 100mV/DIV 100mV/DIV AC AC VOUT COUPLED COUPLED 100mV/DIV AC COUPLED I I L L IL 200mA/DIV 200mA/DIV 200mA/DIV ILOAD I ILOAD LOAD 200mA/DIV 200mA/DIV 200mA/DIV V 20 IN = 3.6V µs/DIV V 20 V 20 IN = 3.6V µs/DIV IN = 3.6V µs/DIV ILOAD = 20mA TO 250mA I I LOAD = 20mA TO 250mA LOAD = 0mA TO 250mA PULSE SKIPPING MODE Burst Mode OPERATION Burst Mode OPERATION 3405A1375 G17 3405A1375 G18 3405A1375 G19 UUUPI FU CTIO SRUN (Pin 1): Run Control Input. Forcing this pin above VIN (Pin 4): Main Supply Pin. Must be closely decoupled 1.5V enables the part. Forcing this pin below 0.3V shuts to GND, Pin 2, with a 2.2µF or greater ceramic capacitor. down the device. In shutdown, all functions are disabled V drawing <1µA supply current. Do not leave RUN floating. OUT (Pin 5): Output Voltage Feedback Pin. An internal resistive divider divides the output voltage down for com- GND (Pin 2): Ground Pin. parison to the internal 0.9V reference voltage. SW (Pin 3): Switch Node Connection to Inductor. This pin MODE (Pin 6): Mode Select Input. To select pulse skip- connects to the drains of the internal main and synchro- ping mode, tie to VIN. Grounding this pin selects Burst nous power MOSFET switches. Mode operation. Do not leave this pin floating. 3405a1375f 5