Diodes AL5811 User Manual

A

60V, LINEAR 75mA ADJUSTABLE CURRENT LED DRIVER

Description

The AL5811 is a Linear LED driver with an adjustable LED current up

to 75mA offering excellent temperature stability and output handling

capability. The AL5811 simplifies the design of linear and isolated or

non-isolated LED drivers by setting the LED current with standard

value resistors.

The AL5811 has an open drain output that can swing from 1V up to

60V enabling it drive long LED chains. Its low 0.5V R

outside of the LED current path and so accuracy is maintained while

minimizing the required overhead to regulate the LED current. This

reduces its power dissipation when compared to traditional linear

LED drivers. This makes it ideal for driving LEDs up to 75mA.

Longer LED chains can be driven by tapping V

where the chain voltage may exceed 60V.

The AL5811 is available in the exposed pad MSOP-8EP and

U-DFN3030-6 packages.

NEW PRODUCT

from the chain,

CC

SET

pin is

Features

• Low Reference Voltage (V

• -40°C to +125°C Temperature Range

• ±6% Typical LED Current Tolerance

• Low Temperature Drift

• 1.0V to 60V Open-Drain Output

• High Power Supply Rejection

• MSOP-8EP and U-DFN3030-6

• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)

• Halogen and Antimony Free. “Green” Device (Note 3)

Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.

2. See http://www.diodes.com for more information about Diodes Incorporated’s definitions of Halogen and Antimony free, "Green" and Lead-Free.

3. Halogen and Antimony free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and <1000ppm antimony compounds.

RSET

= 0.5V)

Pin Assignments

V

1

CC

2

NC

3

NC

4

SET

V

1

CC

NC

2

R

SET

3

U-DFN3030-6

Applications

• Isolated Offline LED Converters

• Linear LED Driver

• LED Signs

• Instrumentation Illumination

(Top View)

MSOP-8EP

(Top View)

Exposed

Pad

8

7

6

5

LED

6

NC

5

GND

4

Typical Applications Circuit

V

IN

V

IN

L5811

LED

NC

GNDR

CIN0.1µF

R

10kΩ

SET

V

R

AL5811

Document number: DS35255 Rev. 1 - 2

CC

AL5811

SET

LED

GND

CIN0.1µF

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V

CC

AL5811

R

SET

R

SET

LED

GND

10kΩ

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Pin Descriptions

Pin Number

MSOP-8EP U-DFN3030-6

1 1

NEW PRODUCT

Name

VCC

RSET 4 3

GND 5 4 Ground Reference Point of Device.

LED 8 6 LED Current Sink Connection.

NC 2, 3, 6, 7 2, 5 Unused

EP Exposed Pad Exposed Pad

Functional Block Diagram

Function

Supply Input. Connect a 0.1μF ceramic capacitor between V

LED Current Setting Pin. Connect a resistor from this pin to GND:

I May also be used to provide PWM dimming functionality

Exposed Pad (bottom). Used to improve thermal impedance of package.

It must be connected to GND directly underneath the package.

LED

= 750/R

SET

and GND as close as possible to the device.

CC

L5811

Absolute Maximum Ratings (@T

Symbol Parameters Ratings Unit

VCC

V

LED

V

R

RSET

I

LED

ESD HBM Human Body Model ESD Protection 1 kV

ESD CDM Charged Device Model ESD protection 1.2 kV

TJ

TST

Notes: 4. VCC pin can be greater or smaller than V

Caution: Stresses greater than the 'Absolute Maximum Ratings' specified above, may cause permanent damage to the device. These are stress ratings only; functional operation of the device at these or any other conditions exceeding those indicated in this specification is not implied. Device reliability may be affected by exposure to absolute maximum rating conditions for extended periods of time. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be taken when handling and transporting these devices

AL5811

Document number: DS35255 Rev. 1 - 2

Supply Voltage Relative to GND Pin (Note 4) -0.3 to +66 V

LED Voltage Relative to GND Pin (Note 4) -0.3 to +66 V

Voltage Relative to GND

SET

LED Pin Current Sink Current Range 85 mA

Operating Junction Temperature -40 to +150 °C

Storage Temperature -55 to +150 °C

= +25°C, unless otherwise specified.)

A

; neither should go below GND.

LED

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-0.3 to +6 V

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Package Thermal Data

θ

Package

JC

Thermal Resistance

Junction-to-case

(Note 5)

Thermal Resistance

Junction-to-Ambient

θ

JA

(Note 5)

P

DIS

= +25°C,

T

A

T

= +125°C

J

MSOP-8EP 37 85°C/W (Note 6) 1.2W

U-DFN3030-6 13 71°C/W (Note 7) 1.40W

Notes: 5. Dominant conduction path via exposed pad.

6. Test condition for MSOP-8EP: Device mounted on FR-4 PCB (51mm x 51mm 2oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer ground plane. For better thermal performance, larger copper pad for heat-sink is needed.

7. Test condition for U-DFN3030-6: Device mounted on FR-4 PCB (51mm x 51mm 2oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer with maximum area ground plane. For better thermal performance, larger copper pad for heat-sink is needed

Recommended Operating Conditions (@T

= +25°C, unless otherwise specified.)

A

NEW PRODUCT

Symbol Parameter Min Max Unit

VCC

V

LED

I

LED

TA

Note: 8. Maximum LED current is also limited by ambient temperature and power dissipation such that junction temperature should be kept less than or equal 125°C.

Supply Voltage Range Relative to GND Pin 3.5 60

OUT Voltage Range Relative to GND Pin 1.0 60

V

LED Pin Current (Note 8) 10 75 mA

Operating Ambient Temperature Range -40 +125 °C

Electrical Characteristics (@T

= +25°C, VCC = 3.5V, V

A

= 1.0 (Note 9), R

LED

= 15kΩ, unless otherwise specified.)

SET

Symbol Parameter Conditions Min Typ Max Unit

V

R

RSET

I

LED

REG

LINE

ICC

I

LEAK

T

SHDN

T

HYS

Note: 9. All voltages unless otherwise stated are measured with respect to GND pin.

Voltage

SET

R

= 37.5kΩ

SET

R

= 10kΩ

Current Accuracy

LED

LED Current Line Regulation

Supply Current

LED Pin Leakage Current

Thermal Shutdown

Thermal Shutdown Hysteresis 20 °C

SET

R

= 15kΩ

SET

VCC = 3.5V to 60V TA = +25°C

3.5V ≤ VCC ≤ 60V

V

= 60V; V

CC

RSET = Open Circuit

LED

= 60V

TA = -40°C to +125°C

T

= +25°C

A

TA = -40°C to +125°C

= +25°C

T

A

TA = -40°C to +125°C

= +125°C

T

A

155 °C

0.5 V

18 20 22

70 75 80

47 50 53

46 54

0.25 %

200 300

350

1 µA

AL5811

Document number: DS35255 Rev. 1 - 2

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L5811

mA

µA

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CUR

RENT

CUR

RENT

CUR

RENT

CUR

REN

T

Typical Performance Characteristics

NEW PRODUCT

80

70

60

50

(mA)

40

30

LED

20

10

0

INPUT VOLTAGE (V)

LED Current vs. Input Voltage

60

50

40

(mA)

R = 15K

SET

L5811

90

80

R = 10K

70

60

(mA)

50

40

30

LED

20

V = 3.5V

CC

10

V = 1.0V

LED

0

-40 25 125 AMBIENT TEMPERATURE (°C)

LED Current vs. Ambient Temperature

80

Ω

70

60

50

(mA)

SET

Ω

R = 10K

SET

R = 37.4K

Ω

R = 15K

SET

R = 15K

SET

Ω

30

40

30

20

LED

10

V = 3.5V

IN

T = +25°C

A

0

1234 78910

0

LED PIN VOLTAGE (V)

LED Current vs. LED Pin Voltage

LED

20

10

0

0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

V = 3.5V

CC

T = +25°C

A

R = 37.4K

SET

INPUT VOLTAGE (V)

LED Current vs. Input Voltage

Ω

AL5811

Document number: DS35255 Rev. 1 - 2

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