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FP6736-1.8-OCT-2017

FP6736

Functional Pin Description

Pin Name

Pin Function

LX

Power Switching Connection. Connect LX to the inductor and output rectifier. Connect components as close to LX

as possible.

GND

Ground.

FB

Feedback Pin. Connect a resistive voltage-divider from the output to FB to set the output voltage.

SHDN

Shutdown Input. Drive SHDN low to turn off the converter. To automatically start the converter, connect SHDN

to VIN. Do not leave SHDN unconnected.

SS

Soft-Start Input. Connect a soft-start capacitor from SS to GND to soft-start the converter. Leave SS open to

disable the soft-start function.

IN

Internal Bias Voltage Input. Connect VIN to the input voltage source. Bypass VIN to GND with a 1µF or greater

capacitor as close to VIN as possible.

Block Diagram

CONTROL

LOGIC

PWM/PFM

CONTROL

1.4MHz

OSCILLATOR

1.23V

VREF

SLOPE

COMPENSATION

PWM

COMPARATOR

DRIVER

CURRENT AMP.

RC

CC

ERROR

AMP.

RS

M1

LX

GND

SS

IN

FB

Soft Start

IN

4µA

SHDN

Figure 5. Block Diagram of FP6736