Fairchild FAN5612 Low-dropout led drivers for white, blue, or any color led Datasheet

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FAN5611/FAN5612/FAN5613/FAN5614
Low-Dropout LED Drivers for White, Blue,
or any Color LED
Features
Description
■ LED drivers for parallel-connected LEDs (2 to 4)
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, RSET. The
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.
■ 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
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.
Applications
■ Cell Phones
■ PDA, DSC, MP3 Players
■ Handheld Computers
■ LCD Display Modules
■ Keyboard Backlight
■ LED Displays
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
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
Low-Dropout LED Drivers for White, Blue, or any Color LED
November 2006
VIN
VIN
VIN
ISET
VCONTROL (3V)
I4
I3
I2
I1
I3
ISET
VCONTROL (3V)
CTRL
RSET
FAN5611
I2
CTRL
Four Diode Control
I4
CTRL
I3
RSET
I2
I1
FAN5613
ON/OFF
ENABLE
ON/OFF
ENABLE
ISET
VCONTROL (3V)
FAN5612
RSET
GND
I1
GND
GND
Three Diode Control with ON/OFF
Four Diode Control With ON/OFF
VIN
I1/I2
ISET
VCONTROL (3V)
CTRL
I3/I4
FAN5614
RSET
ON/OFF
ENABLE
GND
Two Diode Control with ON/OFF
Figure 1. Typical Applications for FAN5611, FAN5612, FAN5613, FAN5614
Pin Assignments
CTRL
1
6
I3
CTRL
1
6
ON/OFF
I2
2
5
I4
I2
2
5
I3
I1
3
4
GND
I1
3
4
GND
FAN5611
CTRL
1
6
ON/OFF
I1/I2
2
5
I3/I4
N/C
3
4
GND
FAN5612
FAN5614
6-LEAD SC-70
TOP VIEW
TOP VIEW
D2
ON/OFF
D1
GND
CTRL
GND
D4
D3
NC
I3
CTRL
I4
I2
GND
I1
FAN5611
FAN5613
2x2mm 6-LEAD MPX
2x2mm 8-LEAD MLP
Figure 2. Pin Assignments for FAN5611, FAN5612, FAN5613, FAN5614
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
2
FAN5611/FAN5612/FAN5613/FAN5614
Typical Applications
Name
Pin #
FAN5611
FAN5612
1
CTRL
CTRL
FAN5613
FAN5614
CTRL
ON/OFF
2
I2
Description
Sets LED Current (see Operational Descripton)
Chip ON/OFF/Disable
I2
Connect to Cathode of LED
I3
Connect to Cathode of LED
I1/I2
3
I1
I1
Connect to Cathode of LED
I4
4
GND
5
I4
GND
GND
Connect to Cathode of LED
N/C
No Connection
GND
Ground
Connect to Cathode of LED
I3
Connect to Cathode of LED
I1
Connect to Cathode of LED
I3/I4
6
I3
Connect to Cathode of LED
Connect to Cathode of LED
ON/OFF
ON/OFF
I2
7
CTRL
8
NC
Chip ON/OFF/Disable
Connect to Cathode of LED
Sets LED Current (see Operational Descripton)
No Connection
Table 2. Pin Descriptions
Notes:
1. The DAP of FAN 5611MPX can be tied to the GND pin or left floating. For better power dissipation, tie to GND.
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
3
FAN5611/FAN5612/FAN5613/FAN5614
Pin Descriptions
The “Absolute Maximum Ratings” are those values beyond which the safety of 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 “Recommended Operating Conditions” 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 TA = 85°C
6-Lead SC70
190
6, 8-Lead MLP
700
I1, I2, I3, I4 Steady State Current
FAN5611/12/13
40
I1/I2, I3/I4 Steady State Current
FAN5614
80
Lead Temperature (Soldering 10 seconds)
300
Junction Temperature
Storage Temperature
-55
Electrostatic Discharge Protection (ESD) Level (1)
HBM
4
CDM
1
mW
mA
°C
150
°C
150
°C
kV
Table 3. Absolute Maximum Ratings
Recommended Operating Conditions
Parameter
LED Cathode Voltage
Min.
Typ.
Max.
Unit
FAN5611, FAN5612, FAN5613
0.3
0.5
1.0
V
FAN5614
0.15
25
85
°C
Ambient Temperature
-40
Table 4. Recommended Operating Conditions
Notes:
2. Using Mil Std. 883E, method 3015.7 (Human Body Model) and EIA/JESD22C101-A (Charge Device Model).
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
4
FAN5611/FAN5612/FAN5613/FAN5614
Absolute Maximum Ratings
VIN = 3.3V to 5.5V, ENABLE = VIN, TA = 25°C unless otherwise noted.
Parameter
Conditions
FAN5611/12/13
ISET = 100µA
VSAT = 300mV
FAN5614
ISET = 100µA
VSAT = 150mV
FAN5611/12/13
VSAT = 300mV
ISET = 100µA
FAN5614
VSAT = 150mV
ISET = 100µA
Current Gain
LED Current (Per Diode)
FAN5611/12/13
VSAT = 300mV
ISET = 100µA
TA = -40°C to 85°C
FAN5614
VSAT = 150mV
ISET = 100µA
TA = -40°C to 85°C
LED to LED Current Matching
Typ.
Max.
140
200
260
20
-3
VIN = 3V
Peak Efficiency
Current in OFF Mode (ISET and II)
Minimum ENABLE “ON Voltage”
(FAN5612, FAN5613, FAN5614)
Min.
Units
mA
3
90
%
%
VEN = 0V
1
µA
ISET = 150µA
2.8
V
(2)
Maximum ENABLE “OFF Voltage”(2)
(FAN5612, FAN5613 FAN5614)
0.5
V
Table 5. DC Electrical Characteristics
Notes:
3. ENABLE “ON” is VEN where II1>20mA @ VI1=0.3V, while ENABLE “OFF” is VEN where II1<1μA @ VI1>0.3V.
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
5
FAN5611/FAN5612/FAN5613/FAN5614
DC Electrical Characteristics
FAN5611/FAN5612/FAN5613/FAN5614
Typical Performance Characteristics
Figure 3. FAN5611/12/13
Output Current vs. Temerature
Figure 4. ISET vs. VCTRL
Figure 5. FAN5611/12/13
LED Current vs. LED Cathode Voltage
Figure 6. FAN5614
LED Current vs. LED Cathode Voltage
Figure 7. FAN5611/12/13
LED Current vs. Set Resistor
Figure 8. FAN5614 LED Current vs. Set Resistor
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
6
Figure 9. FAN5611/12/13/14
Control Voltage Transient Response
Figure 10. FAN5612/13/14
Enable Voltage Transient Response
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
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FAN5611/FAN5612/FAN5613/FAN5614
Typical Performance Characteristics (Continued)
Operational Descripton
The regulated current through each LED is a multiplication of the ISET current. The ISET value is determined by
the RSET value. The ISET value can be calculated as:
VIN
ISET = ILED / Current Gain
VCONTROL
Reference Figure 4, the ISET vs. VCTRL graph, to estimate VCTRL. The value of RSET is calculated according
to the formula:
I4
CTRL
ENABLE
I3
I2
I1
FAN5613
RSET
RSET = (VCONTROL - VCTRL) / ISET
ON/OFF
GND
For example, with VCONTROL = 3V, a 10mA current limit
through the LED results in ISET = 50µA. That translates
to an approximate value of 1.2V for VCTRL, shown in Figure 4. The resulting RSET value that maintains 10mA regulation is 36kΩ.
–
–
–
–
The LED intensity can be adjusted by varying the duty
cycle of a square wave applied to the enable pin. Frequency greater than 100Hz is best to avoid a "flickering"
effect. The maximum operation frequency is 10MHz.
VDROP < 0.3V
VF (at 20mA) < 3.1V (Low VF)
VIN (at 20mA) =VDROP + VF = 3.4V
VIN (at 5mA Typical) ~ 3.1V
where VIN = Single cell Li-ion voltage.
Key advantages:
• No boost circuit is needed for the LCD or keyboard
backlight.
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:
• 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-VF white or blue LEDs, the VIN needs to be
only 300mV higher than the highest VF in the circuit.
Efficiency = ( V IN – V CATHODE ) ⁄ V IN
The lower the VCATHODE, the higher the system efficiency. Efficiency can be further improved by using a
higher VIN with more LEDs, as shown in Example 3.
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 VF white or blue LEDs directly
from single cell Li-ion
When using white or blue low VF LEDs, and utilizing the
drivers low voltage drop, only 3.4V in VIN is needed for
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.
VDROP < 0.3V
VF (at 20mA) < 3.3V to 4.0V (High VF)
VIN (at 20mA) =VDROP + VF = 3.6V to 4.3V
VIN (at 5mA Typical) ~ 3.3V
where VIN = existing bus = 3.3V to 4.3V.
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.
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
ISET
www.fairchildsemi.com
8
FAN5611/FAN5612/FAN5613/FAN5614
Application Information
– VDROP < 0.3V
– VIN_MIN = N ¥ VF + VDROP
– VIN _MAX = N ¥ VF + 5.5V
where VIN = existing bus, boost voltage.
Key advantage:
• No need for current matching resistors and discrete
transistor for brightness control.
VIN
'N' number of
LEDs Per Branch
ISET
I4
VCONTROL
I3
I2
I1
CTRL
FAN5613
RSET
ENABLE
ON/OFF
GND
LED Brightness Control
2. FAN5612
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 RSET, use the ISET
vs. VCTRL graph in Figure 4.
VIN
ISET
VCONTROL
I3
CTRL
I2
I1
FAN5612
RSET
1. FAN5611
ENABLE
VIN
ISET
VCONTROL (3V)
I4
I3
CTRL
RSET
I2
GND
- Analog
Set VCONTROL and RSET for LED current using:
I1
FAN5611
- PWM - 1
200 × ( V CONTROL – V CTRL )
I LED = ------------------------------------------------------------------------R SET
GND
VCONTROL = PWM
- Analog
Set VCONTROL and RSET for LED current using:
– Amplitude sets maximum LED current.
– Pulse width controls between 0 and maximum.
200 × ( V CONTROL – V CTRL )
I LED = ------------------------------------------------------------------------R SET
- PWM - 2
Set VCONTROL and RSET for maximum LED current using:
I LED ∼ 200 × I SET
- PWM
VCONTROL = PWM
ON/OFF = PWM
– Amplitude sets maximum LED current.
– Pulse width controls between 0 and maximum.
– Amplitude has no effect on current.
– Pulse width controls between 0 and maximum.
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
ON/OFF
www.fairchildsemi.com
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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. .
4. FAN5614
VIN
VIN
VCONTROL
ISET
I4
CTRL
RSET
ENABLE
I3
I2
VCONTROL
CTRL
I3/I4
FAN5614
RSET
FAN5613
ON/OFF
ENABLE
ON/OFF
VSS
VSS
- Analog
Set VCONTROL and RSET for LED current using:
- Analog
Set VCONTROL and RSET for LED current using:
I LED
I1/I2
ISET
I1
200 × ( V CONTROL – V CTRL )
I LED = ------------------------------------------------------------------------R SET
200 × ( V CONTROL – V CTRL )
= ------------------------------------------------------------------------R SET
- PWM - 1
VCONTROL = PWM
- PWM - 1
VCONTROL = PWM
– Amplitude sets maximum LED current.
– Pulse width controls between 0 and maximum.
– Amplitude sets maximum LED current.
– Pulse width controls between 0 and maximum.
- PWM - 2
Set VCONTROL and RSET for maximum LED current using:
- PWM - 2
Set VCONTROL and RSET for maximum LED current using:
I LED ∼ 200 × I SET
I LED ∼ 200 × I SET
200 × ( V CONTROL – V CTRL )
I LED = ------------------------------------------------------------------------R SET
ON/OFF = PWM
– Amplitude has no effect on current.
– Pulse width controls between 0 and maximum.
ON/OFF = PWM
– Amplitude has no effect on current.
– Pulse width controls between 0 and maximum.
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
10
FAN5611/FAN5612/FAN5613/FAN5614
3. FAN5613
FAN5611/FAN5612/FAN5613/FAN5614
Mechanical Dimensions
2x2mm 6-Lead MLP
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
11
FAN5611/FAN5612/FAN5613/FAN5614
Mechanical Dimensions
2x2mm 8-Lead MLP
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
12
FAN5611/FAN5612/FAN5613/FAN5614
Mechanical Dimensions
6-Lead SC-70 Package
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
13
FAN5611/FAN5612/FAN5613/FAN5614
© 2003 Fairchild Semiconductor Corporation
FAN5611/FAN5612/FAN5613/FAN5614 Rev. 1.0.9
www.fairchildsemi.com
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