SYNC

DR1

GD1

SE1

VDHC

OutP

VLedFB

CDHC

Faultb

FAULT_CAP

VCC

DIM

Thermal

DMIN

Thermal_Cap

AGND

PGND

EN

VIN

PGND

DR2

GD2

SE2

DR3

GD3

SE3

DR4

GD4

SE4

CFLT

AGND

AGND

Primary power

supply

Voltage

feedback pin

VRAIL

Voltage

output

Fault acknowledgement output

FAULTb

DIM

PWM dimming input

CDHC

RFB1

RFB2

High Power LED Arrays

Q1

Q2

Q3

Q4

RISNS1

RISNS2

RISNS3

RISNS4

RDHC

RTHM1

CVCC

RTHM2

CTHM

RDMIN2

RDMIN1

PGND

PGND

PGND

PGND

PGND

NTC thermistor

couple to LED

arrays

To NTC thermal

sensor

A

B

To thermal

sensor

terminals

A

B

External voltage headroom control

VDHC

5V

0V

LM3464/64A

LM3464, LM3464A

www.ti.com

SNVS652F – APRIL 2010 – REVISED MAY 2013

LED Driver with Dynamic Headroom Control and Thermal Control Interfaces

Check for Samples: LM3464, LM3464A

1

FEATURES

DESCRIPTION

The LM3464/64A is a 4-channel high voltage current

2

•

Wide Input Voltage Range

regulator that provides a simple solution for LED

–

12V-80V (LM3464)

lighting applications. The LM3464/64A provides four

–

12V-95V (LM3464A)

individual current regulator channels and works in

conjunction with external N-channel MOSFETs and

•

Dynamic Headroom Control Ensures Maximum

sense resistors to give accurate driving current for

Efficiency

every

LED

string.

Additionally,

the

Dynamic

•

4 Output Channels With Individual Current

Headroom Control (DHC) output can be interfaced to

Regulation

the external power supply to adjust the LED supply

•

High Channel to Channel Accuracy

voltage to the lowest level that is adequate to

maintain all the string currents in regulation, yielding

•

Digital PWM/Analog Dimming Control Interface

the optimal overall efficiency.

•

Resistor Programmable Dimming Frequency

Digital PWM or analog voltage signals can be used to

and Minimum Duty Cycle (Analog Dimming

control the duty cycle of the all the channels. When

Mode)

analog control is used, the dimming frequency can be

•

Direct Interface to Thermal Sensor

programmed via an external capacitor. A minimum

•

Fault Detection

duty cycle control is provided in the conditions that

the

analog

dimming

is

configured

as

thermal

•

Over Temperature Protection

feedback.

•

Thermal Shutdown

Protection features include VIN under-voltage lock-

•

Under Voltage Lockout

out, LED open/short circuit and over-temperature fault

•

Thermal Enhanced TSSOP-28 Package

signaling to the system controller.

APPLICATIONS

•

Streetlights

•

Solid State Lighting Solutions

Typical Application

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2010–2013, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.