intersil ISL97632 DATA SHEET

®

www.BDTIC.com/Intersil

ISL97632

Data Sheet February 22, 2008

White LED Driver with Digital Dimming

The ISL97632 represents an efficient and highly integrated
PWM boost LED driver that is suitable for 1.8” to 3.5” LCDs
that employ 2 to 6 white LEDs for backligh ti n g. With
integrated Schottky diode, OVP, and dynamic digital
dimming capability , the ISL97632 provides a simple, reliable,
and flexible solution to the backlight designers.

The ISL97632 features a simple single-wire digital interface
that provides a 5-bit dimming control. The dimming signal
adjusts the FB voltage and therefore the LED brightness in a
DC manner in 32 linear steps. An EN pin can be used to
provide a zero brightness setting or shutdown power saving
function.

The ISL97632 is available in the 8 Ld TDFN (2mmx3mm)
package. There are 14V , 18V, and 26V OVP options that are
suitable for 3, 4, and 6 LEDs backlight applications
respectively. The ISL97632 is specified for operation over
the -40°C to +85°C ambient temperature at input voltage
from 2.4V to 5.5V.

Pinout

ISL97632

(8 LD 2x3 TDFN)

TOP VIEW

GND

VIN

EN

SDIN

1
2
3
4

LX

8

VOUT

7

FBSW

6

FB

5

Typical Application Circuit

VIN

EN

SDIN

GND

10µH or 22µH

LX

VOUT

FBSW

FB

VIN

FN9239.3

Features

• 5-Bit Digital Dimming Control

• Drives up to 6 LEDs in Series

• OVP (14V , 18V and 26V for 3, 4, and 6 LEDs applications)

• Integrated Schottky Diode

• 2.4V to 5.5V input

• 86% Efficiency

• 1.4MHz Switching Frequency Allows Small LC

• Enable for Shutdown Function or Zero Brightness Setting

• 1µA Shutdown Current

• Internally Compensated

• 8 Ld TDFN (2mmx3mm)

• Pb-Free (RoHS Compliant)

Applications

• LED backlighting for

- Cell phones

- Smartphones

-MP3

-PMP

- Automotive Navigation Panel

- Portable GPS

Ordering Information

PACKAGE

PART NUMBER

(Note)

ISL97632IRT14Z-T* ELB 8 Ld 2x3 TDFN L8.2x3A
ISL97632IRT14Z-TK* ELB 8 Ld 2x3 TDFN L8.2x3A
ISL97632IRT18Z-T* ELC 8 Ld 2x3 TDFN L8.2x3A
ISL97632IRT18Z-TK* ELC 8 Ld 2x3 TDFN L8.2x3A
ISL97632IRT26Z-T* ELD 8 Ld 2x3 TDFN L8.2x3A
ISL97632IRT26Z-TK* ELD 8 Ld 2x3 TDFN L8.2x3A
*Please refer to TB347 for details on reel specifications.

NOTE: These Intersil Pb-free plastic packaged products employ
special Pb-free material sets; molding compounds/die attach
materials and 100% matte tin plate PLUS ANNEAL - e3 termination
finish, which is RoHS compliant and compatible with both SnPb and
Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or exceed
the Pb-free requirements of IPC/JEDEC J STD-020.

PART

MARKING

TAPE AND REEL

(Pb-Free)

PKG.

DWG.#

1

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774

| Intersil (and design) is a registered trademark of Intersil Americas Inc.

All other trademarks mentioned are the property of their respective owners.

Copyright Intersil Americas Inc. 2006-2008. All Rights Reserved

ISL97632

www.BDTIC.com/Intersil

Absolute Maximum Ratings (T

Input Voltage (V

LX Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to 28V

FBSW Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to 28V

All Other Pins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to 6V

) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to 6V

IN

= +25°C) Thermal Information

A

Thermal Resistance (Typical, Note 1) θ

TDFN Package (Notes 1, 2). . . . . . . . . 70 10.5

Maximum Junction Temperature . . . . . . . . . . . . . . . . . . . . . .+125°C

Storage Temperature . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C

Lead Temperature (S oldering 10s) . . . . . . . . . . . . . . . . . . . .+300°C

(°C/W) θJC (°C/W)

JA

Operating Conditions

Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C

CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.

IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed over temperature of -40°C to +85°C unless otherwise stated. Typical va lues are for
information purposes only at TJ = TC = TA = +25°C.

NOTE:

1. θ

is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See

JA

Tech Brief TB379.

2. For θ

Electrical Specifications V

PARAMETER DESCRIPTION CONDITION MIN TYP MAX UNIT

R

t

LOGIC-LOAD

t

LOGIC-HIGH

, the “case temp” location is the center of the exposed metal pad on the package underside.

JC

= VEN = 3V

IN

V

IN

I

IN

Fsw Switching Frequency 1,300 1,450 1,600 kHz

DMAX Maximum Duty Cycle 90 95 %

I

LIM

R

SW(LX)

ILEAK LX Switch Leakage Current VLX = 28V 1 μA

VFB Feedback Voltage Serial interface setting = 15 (center) 90 95 100 mV

IFB FB Pin Bias Current VFB = 95mV 1 μA

SW(FBSW)

V

DIODE

OVP Overvoltage Protection ISL97632IRT14Z 14 V

VIL Logic Low Voltage 0.6 V

VIH Logic High Voltage 1.5 V

t

LOGIC

t

LOGIC

Supply Voltage 2.4 5.5 V
Supply Current EN = 3V, enabled, not switching 0.8 1.5 mA

EN = 0V, disabled 1 μA

LX Current 400 470 mA
LX Switch ON-Resistance ILX = 100mA 900 mΩ

Serial interface setting = S (S = 0,1..31) 9.8 + 5.68 x S mV
Serial interface setting = 0

FBSW Switch ON-Resistance 10 Ω
Schottky Diode Forward

Voltage

1 Timing Range for Logic 1 SDIN = low 15 45 μs
0 Timing Range for Logic 0 SDIN = low 90 120 μs

Timing Range for Load SDIN = low 215 μs
Minimum Valid SDIN High

Time

IDIODE = 100mA, TA = +25°C 600 850 mV

ISL97632IRT18Z 18 V
ISL97632IRT26Z 26 28 V

SDIN = high 3 μs

9.8 mV

2

FN9239.3

February 22, 2008

Block Diagram

www.BDTIC.com/Intersil

VIN (2.4V to 5.5V)

CIN

ISL97632

L

VIN EN LX

1.4MHZ OSCILLATOR AND RAMP
GENERATOR

PWM

COMPARATOR

GM AMP
COMPENSATION

SDIN

PWM LOGIC

CONTROLLER

GM

AMPLIFIER

CURRENT

10 - 186mV

SERIAL

INTERFACE

ISL97632

FET

DRIVER

SENSE

EN

BANDGAP

REFERENCE

GENERATOR

V

OUT

GND

FBSW

FB

2 to 6 LEDs

RSET

C

OUT

Pin Descriptions

PIN

NUMBER

1 GND Ground Pin. Connect to local ground.
2 VIN Input Supply Pin. Connect to the input supply voltag e, t he ind uctor a nd t he inp ut sup ply decoup ling

3 EN Enable Pin. Connect to enable signal to turn-on or off the device. Active High.
4 SDIN Single-Wire XSD Digital Interface.
5 FB Feedback Pin. Connect to the cathode of bottom LED and the sense resistor.
6 FBSW Optional FB Disconnect Switch.
7 VOUT Output Pin. Connect to the ano de o f t he t op L ED and t he o utpu t f ilte r ca pacitor.
8 LX Switching Pin. Connect to inductor.

PIN

NAME DESCRIPTION

capacitor.

3

FN9239.3

February 22, 2008