Connection Diagram

18-Bump Thin Micro SMD Package, Large Bump

NS Package Number TLA18

20128002

Pin Description

Pin #s

Pin Names

Pin Descriptions

C1

V

IN

Input voltage. Input range: 2.7V to 5.5V.

D2

PWR GND

Power Ground

A3

PWR P

OUT

Charge pump output. Approximately 1.5xV

IN

A1, B2, A5, E1

C1+, C1-, C2+,

C2-

Flying capacitor connections.

D6, E5, D4, E3

D1, D2, D3, D4

LED Outputs - Group A

C5, B4, C3

SIG P

OUT

Signal P

B6

EN

Enable for Charge Pump and LEDs (current outputs). Logic input.

High = LEDs ON. Low = LEDs OFF.

Pulsing this pin with a PWM signal (100Hz-1kHz) can be used to dim LEDs.

A7

SIG GND

Signal Ground. Tie pin externally to PWR GND

E7

I

SET

Placing a resistor (R

Current = 100 x (1.25V ÷ R

C7

NC

No Connect

Operational States

EN

Mode of Operation

L

Shutdown

H

Charge Pump Enabled. LEDs ON.

Ordering Information

Order Information

Package

Supplied As

LM27953TL

TLA18 Micro SMD

250 Units, Tape & Reel

LM27953TLX

3000 Units, Tape & Reel

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