Datasheet FAN5611, FAN5612, FAN5613, FAN5614 Datasheet (Fairchild)

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FAN5611/FAN5612/FAN5613/FAN5614 Low-Dropout LED Drivers for White, Blue, or any Color LED

Low-Dropout LED Drivers for White, Blue, or any Color LED

November 2006

Features

■ LED drivers for parallel-connected LEDs (2 to 4)

■ Ultra-low voltage drop (< 300mV) to support direct

Li-ion applications

■ No EMI, no switching noise

■ No external components needed for current matching

■ Both analog and PWM brightness control

■ FAN5611, FAN5613 feature up to 160mA bias current

(up to 40mA for each LED)

■ FAN5612 features up to 120mA bias current

(up to 40mA for each LED)

■ FAN5614 features up to 160mA bias current

(up to 80mA for each LED)

■ Enable/Shutdown control (FAN5612, FAN5613,

FAN5614)

■ Shutdown current < 1μA

■ Small footprint SC-70 and MLP

Applications

■ Cell Phones

■ PDA, DSC, MP3 Players

■ Handheld Computers

■ LCD Display Modules

■ Keyboard Backlight

■ LED Displays

Description

The FAN5611/12/13/14 low-dropout product family is designed to drive two to four parallel LEDs, providing matched current source bias for all color LEDs. The LED current is set by an external resistor, R FAN5611/13 supports four parallel LEDs with up to 160mA bias current (up to 40mA per output). The FAN5612 supports three LEDs with up to 120mA bias current (40mA per output). The FAN5614 drives two high-current LEDs (80mA per output). Pin I1 should always be connected to an LED to provide a matched current for any additional LEDs.

The FAN5612/13 and 14 are selected using an ENABLE pin. When the chip is not selected (ENABLE pin is LOW), the supply current drops to less than 1µA.

The FAN5611, FAN5612, and FAN5614 are available in an SC-70 package. The FAN5611 and FAN5613 are available in MLP packages.

SET

. The

Ordering Information

Product Number Package Type Order Code

FAN5611 6-Lead SC-70 / 2x2mm 6-Lead MLP FAN5611S7X / FAN5611MPX FAN5612 6-Lead SC-70 FAN5612S7X FAN5613 2x2mm 8-Lead MLP FAN5613MPX FAN5614 6-Lead SC-70 FAN5614S7X

Table 1. Ordering Information

Typical Applications

FAN5611/FAN5612/FAN5613/FAN5614

V

IN

I

V

CONTROL

SET

(3V

)

CTRL

R

SET

Four Diode Control

Figure 1. Typical Applications for FAN5611, FAN5612, FAN5613, FAN5614

Pin Assignments

FAN5611

GND

CONTROL

V

IN

I

SET

(3V)

R

SET

ENABLE

I3

FAN5613

GND

I2

I1

I4

CTRL

ON/OFF

Four Diode Control With ON/OFF

V

IN

I1I2I3I4

V

(3V)

CONTROL

ENABLE

V

IN

V

CONTROL

I

(3V)

R

ENABLE

I3

I

SET

CTRL

R

SET

ON/OFF

Three Diode Control with ON/OFF

SET

CTRL

SET

ON/OFF

Two Diode Control with ON/OFF

I2

FAN5612

GND

FAN5614

GND

I1

I3/I4I1/I2

V

CTRL

I2

I1

FAN5611

1

6

25

4

3

I3

I4

GND

CTRL

I2

I1

1

6

25

34

ON/OFF

I3

GND

I1/I2

FAN5612

6-LEAD SC-70

TOP VIEW

ON/OFF

D2

CTRL

D3

GND

D1

GND

D4

GND

FAN5611

2x2mm 6-LEAD MPX

Figure 2. Pin Assignments for FAN5611, FAN5612, FAN5613, FAN5614

2x2mm 8-LEAD MLP

TOP VIEW

I3

I4

FAN5613

N/C

1

6

25

34

FAN5614

NC

CTRL

I2

I1

ON/OFFCTRL

I3/I4

GND

Pin Descriptions

Name

Pin #

1 CTRL CTRL CTRL Sets LED Current (see Operational Descripton)

ON/OFF Chip ON/OFF/Disable

2 I2 I2 Connect to Cathode of LED

I3 Connect to Cathode of LED

I1/I2

3 I1 I1 Connect to Cathode of LED

I4 Connect to Cathode of LED

N/C No Connection 4GNDGNDGNDGNDGround 5 I4 Connect to Cathode of LED

I3 Connect to Cathode of LED

I1 Connect to Cathode of LED

I3/I4 Connect to Cathode of LED

6 I3 Connect to Cathode of LED

ON/OFF ON/OFF Chip ON/OFF/Disable

I2 Connect to Cathode of LED 7 CTRL Sets LED Current (see Operational Descripton) 8 NC No Connection

Table 2. Pin Descriptions

DescriptionFAN5611 FAN5612 FAN5613 FAN5614

FAN5611/FAN5612/FAN5613/FAN5614

Notes:

1. The DAP of FAN 5611MPX can be tied to the GND pin or left floating. For better power dissipation, tie to GND.

Absolute Maximum Ratings

The “Absolute Maximum Ratings” are those values beyond wh ich the safety o f the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum ratings. The “R ecommended Operating Cond itions” table defines the conditions for actual device operation.

Parameter Min. Max. Unit

VI1, VI2, VI3, VI4 and ENABLE Voltage to GND -0.3 6.0 V CTRL Voltage to GND -0.3 3.0 Power Dissipated by package at T

I1, I2, I3, I4 Steady State Current FAN5611/12/13 40 mA I1/I2, I3/I4 Steady State Current FAN5614 80 Lead Temperature (Soldering 10 seconds) 300 °C Junction Temperature 150 °C Storage Temperature -55 150 °C Electrostatic Discharge Protection (ESD) Level

Table 3. Absolute Maximum Ratings

= 85°C 6-Lead SC70 190 mW

A

6, 8-Lead MLP 700

(1)

HBM 4 kV CDM 1

FAN5611/FAN5612/FAN5613/FAN5614

Recommended Operating Conditions

Parameter Min. Typ. Max. Unit

LED Cathode Voltage FAN5611, FAN5612, FAN5613 0.3 0.5 1.0 V

FAN5614 0.15

Ambient Temperature -40 25 85 °C

T able 4. Recommended Operating Conditions Notes:

2. Using Mil Std. 883E, method 3015.7 (Human Body Model) and EIA/JESD22C101-A (Charge Device Model).

DC Electrical Characteristics

VIN = 3.3V to 5.5V, ENABLE = VIN, TA = 25°C unless otherwise noted.

Parameter Conditions Min. Typ. Max. Units

= 100µA

I

FAN5611/12/13

Current Gain

FAN5614

LED Current (Per Diode)

FAN5611/12/13

FAN5614

FAN5611/12/13

LED to LED Current Matching

FAN5614

Peak Efficiency V Current in OFF Mode (I Minimum ENABLE “ON Voltage”

and II)V

SET

(2)

(FAN5612, FAN5613, FAN5614) Maximum ENABLE “OFF Volt age”

(2)

(FAN5612, FAN5613 FAN5614)

Table 5. DC Electrical Characteristics Notes:

3. ENABLE “ON” is V

where II1>20mA @ VI1=0.3V, while ENABLE “OFF” is V

EN

SET

V

= 300mV

SAT

I

= 100µA

SET

V

= 150mV

SAT

= 300mV

V

SAT

I

= 100µA

SET

= 150mV

V

SAT

= 100µA

I

SET

V

= 300mV

SAT

I

= 100µA

SET

TA = -40°C to 85°C

V

= 150mV

SAT

= 100µA

I

SET

TA = -40°C to 85°C

= 3V 90 %

IN

= 0V 1 µA

EN

I

= 150µA 2.8 V

SET

140 200 260

20 mA

-3 3

0.5 V

where II1<1μA @ VI1>0.3V.

EN

FAN5611/FAN5612/FAN5613/FAN5614

%

Typical Performance Characteristics

FAN5611/FAN5612/FAN5613/FAN5614

Figure 3. FAN5611/12/13

Output Current vs. Temerature

Figure 5. FAN5611/12/13

LED Current vs. LED Cathode Voltage

Figure 4. I

SET

vs. V

CTRL

Figure 6. FAN5614

LED Current vs. LED Cathode Voltage

Figure 7. FAN5611/12/13

Figure 8. FAN5614 LED Current vs. Set Resistor

LED Current vs. Set Resistor

Typical Performance Characteristics (Continued)

FAN5611/FAN5612/FAN5613/FAN5614

Figure 9. FAN5611/12/13/14

Control Voltage Transient Response

Figure 10. FAN5612/13/14

Enable Voltage Transient Response

Application Information

Operational Descripton

The regulated current through each LED is a multiplication of the I the R

SET

I

= I

SET

LED

Reference Figure 4, the I mate V

CTRL

to the formula: R

= (V

SET

For example, with V through the LED results in I to an approximate value of 1.2V for V ure 4. The resulting R ulation is 36kΩ.

The LED intensity can be adjusted by varying the duty cycle of a square wave applied to the enable pin. Fr equency greater than 100Hz is best to avoid a "flickering" effect. The maximum operation frequency is 10MHz.

Efficiency Considerations

The FAN561X driver’s low-dropout architecture can significantly improve the efficiency compared to using simple ballast resistors. The system efficiency, defined as the ratio between the LEDs’ power and the input supplied power, can be calculated as:

Efficiency V

The lower the V ciency. Efficiency can be further improved by using a higher V

Application Notes

The ultra-low voltage drop across the FAN561X series of LED drivers allows the devices to drive white, blue, and other color LEDs in a wide range of input voltages. The driver can be used in many applications. Although only the FAN5613 is shown in all three examples, any of the FAN561X-series LED drivers can be used in the applications presented, due to their similar operation.

Example 1: Drive low V from single cell Li-ion

When using white or blue low VF LEDs, and utilizing the drivers low voltage drop, only 3.4V in V the full 20mA LED current. At 3.1V, there is 5mA typical current available for the LEDs. The single cell Li-ion is utilized in applications like cell phones or digital still cameras. In most cases, the Li-ion battery voltage level only goes down to 3.0V voltage level, not down to the full discharge level (2.7V) before requesting the charger.

current. The I

SET

value. The I

SET

value is determined by

SET

value can be calculated as:

/ Current Gain

vs. V

. The value of R

CONTROL

INVCATHODE

CATHODE

with more LEDs, as shown in Example 3.

IN

SET

is calculated according

SET

- V

) / I

CTRL

CONTROL

SET

= 3V, a 10mA current limit

= 50µA. That translates

SET

value that maintains 10mA reg-

–()VIN⁄=

, the higher the system effi-

white or blue LEDs directly

F

graph, to esti-

CTRL

, shown in Fig-

CTRL

is needed for

IN

V

IN

I

V

CONTROL

ENABLE

–V

DROP

–V

F (at 20mA)

–V

IN (at 20mA) =VDROP

–V

IN (at 5mA Typical)

where V

= Single cell Li-ion voltage.

IN

SET

CTRL

R

SET

ON/OFF

< 0.3V

< 3.1V (Low VF)

I4

~ 3.1V

I3

FAN5613

GND

+ VF = 3.4V

I2

I1

Key advantages:

• No boost circuit is needed for the LCD or keyboard backlight.

• Drivers are directly connected to a Li-ion battery.

• No EMI, no switching noise, no boost efficiency lost, no capacitor, and no inductor.

Example 2: Drive high VF white or blue LEDs from existing bus from 4.0V to 5.5V

High VF white or blue LEDs have forward voltage drop in the range of 3.2V to 4.0V. Driving these LEDs with the maximum current of 20mA for maximum brightness, usually requires a boost circuit for a single cell Li-ion voltage range. In some cases, there is already a voltage bus in the system, which can be utilized. Due to the ultralow voltage drop of the FAN561X series of LED drivers to drive high-V only 300mV higher than the highest V

–V –V –V –V

where V

white or blue LEDs, the VIN needs to be

F

< 0.3V

DROP F (at 20mA) IN (at 20mA) =VDROP IN (at 5mA Typical)

IN

< 3.3V to 4.0V (High VF)

+ VF = 3.6V to 4.3V

~ 3.3V

= existing bus = 3.3V to 4.3V.

in the circuit.

F

Key advantages:

• No boost circuit is needed for LCD or keyboard backlight.

• Driver utilizes the existing bus.

• Ultra-low voltage drop provides the full 20mA LED current at the lowest possible voltage level.

FAN5611/FAN5612/FAN5613/FAN5614

Example 3: Drive white, blue, red, amber LEDs string

Assuming a boost circuit or existing voltage bus, the FAN561X series of LED drivers can be used to drive a whole string of LEDs with flexible brightness control via analog and/or PWM. .

V

IN

'N' number of LEDs Per Branch

I

V

CONTROL

ENABLE

SET

CTRL

R

SET

FAN5613

ON/OFF

GND

I1I2I3I4

LED Brightness Control

All of the FAN561X LED drivers feature analog and PWM controls to give designers flexible brightness control. These control methods can be applied to the circuit in two different ways to provide more flexibility than other solutions. To determine the value of R vs. V

graph in Figure 4.

CTRL

1. FAN5611

V

IN

, use the I

SET

–V –V –V

< 0.3V

DROP IN_MIN IN _MAX

= N ¥ VF + V

DROP

= N ¥ VF + 5.5V

where VIN = existing bus, boost voltage.

Key advantage:

• No need for current matching resistors and discrete transistor for brightness control.

2. FAN5612

V

IN

V

CONTROL

ENABLE

I

SET

R

SET

ON/OFF

I3

CTRL

I2

FAN5612

GND

I1

I

SET

(3V

V

CONTROL

)

R

SET

CTRL

FAN5611

GND

- Analog

Set V

I

LED

CONTROL

and R

200 V

-------------------------------------------------------------------------=

for LED current using:

SET

R

–()×

SET

CONTROLVCTRL

- PWM

V

CONTROL

= PWM

– Amplitude sets maximum LED current. – Pulse width controls between 0 and maximum.

I1I2I3I4

- Analog

Set V

CONTROL

and R

for LED current using:

SET

- PWM - 1

I

LED

V

CONTROL

200 V

-------------------------------------------------------------------------=

= PWM

CONTROLVCTRL

R

–()×

SET

– Amplitude sets maximum LED current. – Pulse width controls between 0 and maximum.

- PWM - 2

Set V

I

LED

CONTROL

200 I

×∼

and R

SET

for maximum LED current using:

SET

ON/OFF = PWM

– Amplitude has no effect on current. – Pulse width controls between 0 and maximum.

FAN5611/FAN5612/FAN5613/FAN5614

3. FAN5613

V

IN

I

V

CONTROL

ENABLE

R

SET

I4

CTRL

SET

ON/OFF

- Analog

Set V

I

LED

CONTROL

and R

200 V

-------------------------------------------------------------------------=

CONTROLVCTRL

- PWM - 1

V

CONTROL

= PWM

– Amplitude sets maximum LED current. – Pulse width controls between 0 and maximum.

- PWM - 2

Set V

I

LED

CONTROL

200 I

×∼

and R

SET

ON/OFF = PWM

– Amplitude has no effect on current. – Pulse width controls between 0 and maximum.

I3

I2

I1

FAN5613

V

SS

for LED current using:

SET

–()×

R

SET

for maximum LED current using:

SET

4. FAN5614

V

IN

I

V

CONTROL

ENABLE

SET

R

SET

ON/OFF

CTRL

FAN5614

- Analog

Set V

I

LED

CONTROL

and R

200 V

-------------------------------------------------------------------------=

for LED current using:

SET

R

–()×

SET

CONTROLVCTRL

- PWM - 1

V

CONTROL

= PWM

– Amplitude sets maximum LED current. – Pulse width controls between 0 and maximum.

- PWM - 2

Set V

I

LED

I

LED

CONTROL

200 I

×∼

200 V

-------------------------------------------------------------------------=

and R

SET

for maximum LED current using:

SET

R

–()×

SET

CONTROLVCTRL

ON/OFF = PWM

– Amplitude has no effect on current. – Pulse width controls between 0 and maximum.

I3/I4I1/I2

V

SS

Mechanical Dimensions

2x2mm 6-Lead MLP

FAN5611/FAN5612/FAN5613/FAN5614

Mechanical Dimensions

2x2mm 8-Lead MLP

FAN5611/FAN5612/FAN5613/FAN5614

Mechanical Dimensions

6-Lead SC-70 Package

FAN5611/FAN5612/FAN5613/FAN5614