Preliminary

ML0308

PIN FUNCTION DESCRIPTION

Pin

Description

SW (Pin 1)

This pin is the power side of the external inductor and must be connected to the external

Schottky diode. It provides the output current to the load. Since the boost converter

operates in a current loop mode, the output voltage can range up to 16V but shall not

exceed this limit.

GND (Pin 2)

This pin is the system ground for the ML0308 and carries both the power and the analog

signals. High quality ground must be provided to avoid spikes and/or uncontrolled

operation. Care must be observed to avoid high−density current flow in a limited PCB

copper track so arobust ground plane connection is recommended.

FB (Pin 3)

This pin provides the output current range adjustment by means of a sense resistor

connected to the internal analog control circuitry.

EN (Pin 4)

This pin is the chip-enable Pin. Ground this pin to shutdown the chip. Apply a clock

with different duty ratio to control brightness of the LEDs.

VIN (Pin 5)

The external voltage supply is connected to this pin. A high quality reservoir capacitor

must be connected across pin 5 and Ground to achieve the specified output voltage

parameters. A 4.7uF/6.3 V, low ESR capacitor must be connected as close as possible

across pin 5 and ground pin 2.

INTERNAL BLOCK DIAGRAM

Figure 2: Internal block diagram