Connection Diagram

20003302

8 Lead Mini SO8 Package (MSOP-8 Package)

Package Marking and Ordering Information

Order Number

Package Type

Package Marking

Supplied As:

LM3477MM

MSOP-8

S13B

1000 units on Tape and Reel

LM3477MMX

MSOP-8

S13B

3500 units on Tape and Reel

LM3477AMM

MSOP-8

S13A

1000 units on Tape and Reel

LM3477AMMX

MSOP-8

S13A

3500 units on Tape and Reel

Pin Description

Pin Name

Pin Number

Description

I

SEN

1

Current sense input pin. Voltage generated across an external sense resistor is fed

into this pin.

COMP/SD

2

Compensation pin. A resistor-capacitor combination connected to this pin provides

compensation for the control loop. Pull this pin below 0.65V to shutdown.

FB

3

Feedback pin. The output voltage should be adjusted using a resistor divider to

provide 1.270V at this pin.

GND

4

Ground pin.

SW

5

Switch Node. Source of the external MOSFET is connected to this node.

DR

6

Drive pin. The gate of the external MOSFET should be connected to this pin.

CB

7

Boot-strap pin. A capacitor must be connected between this pin and SW pin (pin 5)

for proper operation. The voltage developed across this capacitor provides the gate

drive for the external MOSFET.

V

IN

8

Power Supply Input pin.

www.national.com

2