A1

A2

B1

B2

B3

Top View

A3

C2

C1

C3

D2

D3

A4

B4

C4

D4

D1

LM3554

www.ti.com

SNVS549A – JUNE 2009 – REVISED APRIL 2011

Connection Diagram

Pin Functions

Pin Descriptions

Pin

Name

Function

A1

LED1

High-Side Current Source Output for Flash LED.

A2, B2

OUT

Step-Up DC/DC Converter Output.

A3, B3

SW

Drain Connection for Internal NMOS and Synchronous PMOS Switches.

A4, B4

GND

Ground

B1

LED2

High-Side Current Source Output for Flash LED.

LEDI/NTC

Configurable as a High-Side Current Source Output for Indicator LED or Threshold Detector for LED

C1

Temperature Sensing.

TX1/TORCH/GPIO Configurable as a RF Power Amplifier Synchronization Control Input (TX1), a Hardware Torch

C2

1

Enable (TORCH), or a programmable general-purpose logic Input/Output (GPIO1).

C3

STROBE

Active High Hardware Flash Enable. Drive STROBE high to turn on Flash pulse.

C4

IN

Input Voltage Connection. Connect IN to the input supply, and bypass to GND with a minimum

4.7µF ceramic capacitor.

D1

ENVM/TX2/GPIO2 Configurable as an Active High Voltage Mode Enable (ENVM), Dual Polarity Power Amplifier

/INT

Synchronization Input (TX2), or Programmable General Purpose Logic Input/Output (GPIO2).

D2

SDA

Serial Data Input/Output.

D3

SCL

Serial Clock Input.

D4

HWEN

Active Low Hardware Reset.

These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam

during storage or handling to prevent electrostatic damage to the MOS gates.

Absolute Maximum Ratings

(1) (2)

-0.3V to 6V

Internally Limited

+150°C

Storage Temperature Range

-65°C to +150°C

Maximum Lead Temperature (Soldering)

(4)

(1)

Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings are conditions under

which operation of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed

performance limits and associated test conditions, see the Electrical Characteristics table.

(2)

All voltages are with respect to the potential at the GND pin.

(3)

(4)

For detailed soldering specifications and information, please refer to National Semiconductor Application Note 1112: Micro SMD Wafer

Level chip Scale Package (AN-1112)

Copyright © 2009–2011, Texas Instruments Incorporated

Submit Documentation Feedback

3

Product Folder Links: LM3554