4

March 2007

KB3408

Kingbor Technology Co.,Ltd

TEL:(86)0755-26508846 FAX:(86)0755-26509052

(From Figure 1a Except for the Resistive Divider Resistor Values)

Start-Up from Shutdown

Load Step

Load Step

RUN

2V/DIV

500mA/DIV

2V/DIV

40

µs/DIV

500mA/DIV

500mA/DIV

100mV/DIV

AC COUPLED

20

µs/DIV

500mA/DIV

500mA/DIV

100mV/DIV

AC COUPLED

20

µs/DIV

Load Step

Load Step

500mA/DIV

500mA/DIV

100mV/DIV

AC COUPLED

20

µs/DIV

500mA/DIV

500mA/DIV

100mV/DIV

AC COUPLED

20

µs/DIV

RUN (Pin 1): Run Control Input. Forcing this pin above

1.5V enables the part. Forcing this pin below 0.3V shuts

down the device. In shutdown, all functions are disabled

drawing <1

µA supply current. Do not leave RUN floating.

GND (Pin 2): Ground Pin.

SW (Pin 3): Switch Node Connection to Inductor. This pin

connects to the drains of the internal main and synchro-

nous power MOSFET switches.

to GND, Pin 2, with a 2.2

µF or greater ceramic capacitor.

back voltage from an external resistive divider across the

output.

Output Volt-

age Feedback Pin. An internal resistive divider divides the

output voltage down for comparison to the internal refer-

ence voltage.

TYPICAL PERFORMANCE CHARACTERISTICS

PIN FUNCTIONS