Connection Diagram

10135502

8 Lead Mini SO8 Package (MSOP-8 Package)

Package Marking and Ordering Information

Order Number

Package Type

Package Marking

Supplied As:

LM3478MM

MSOP-8

S14B

1000 units on Tape and

Reel

LM3478MMX

MSOP-8

S14B

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

2

Compensation pin. A resistor, capacitor combination connected to

this pin provides compensation for the control loop.

FB

3

Feedback pin. The output voltage should be adjusted using a

resistor divider to provide 1.26V at this pin.

AGND

4

Analog ground pin.

PGND

5

Power ground pin.

DR

6

Drive pin of the IC. The gate of the external MOSFET should be

connected to this pin.

FA/SD

7

Frequency adjust and Shutdown pin. A resistor connected to this

pin sets the oscillator frequency. A high level on this pin for

≥ 30µs

will turn the device off. The device will then draw less than 10µA

from the supply.

V

IN

8

Power Supply Input pin.

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