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LED Drivers for High Power LEDs
BDTIC
ILD4120
1200 mA Step Down LED Driver
Data Sheet
Revision 6.0, 2011-10-10
Industrial and Multimarket
www.BDTIC.com/infineon
BDTIC
Edition 2011-10-10
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2011 Infineon Technologies AG
All Rights Reserved.
Legal Disclaimer
The information given in this document shall in no event be regarded as a guarantee of conditions or
characteristics. With respect to any examples or hints given herein, any typical values stated herein and/or any
information regarding the application of the device, Infineon Technologies hereby disclaims any and all warranties
and liabilities of any kind, including without limitation, warranties of non-infringement of intellectual property rights
of any third party.
Information
For further information on technology, delivery terms and conditions and prices, please contact the nearest
Infineon Technologies Office (www.infineon.com).
Warnings
Due to technical requirements, components may contain dangerous substances. For information on the types in
question, please contact the nearest Infineon Technologies Office.
Infineon Technologies components may be used in life-support devices or systems only with the express written
approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure
of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support
devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain
and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may
be endangered.
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ILD4120
1200 mA Step Down LED Driver
Revision History
Page or Item
Subjects (major changes since previous revision)
Revision 6.0, 2011-10-10
All
Preliminary data sheet version replaced by final data sheet version
Table 2
Max. output current and power dissipation updated
Figure 2
Power dissipation updated
Table 4
EN propagation delay added
Table 5
PWM propagation delay added
Figure 4
Figure about maximum LED current contrast ratio added
BDTIC
Chapter 6.4
Figures with 100 mΩ sense resistor updated
Revision 5.0, 2011-08-23
All
Initial version of preliminary data sheet
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Last Trademarks Update 2011-02-24
Data Sheet
3
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ILD4120
1200 mA Step Down LED Driver
Table of Contents
Table of Contents
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2
Product Brief . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3
Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4
Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5
5.1
5.2
5.3
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Analog and Digital Dimming Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switching Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13
13
13
15
6
6.1
6.2
6.3
6.4
Basic Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Setting the average LED current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dimming of the LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Temperature Protection Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switching Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16
16
16
19
20
7
Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
8
9
BDTIC
Evaluation Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Data Sheet
4
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ILD4120
1200 mA Step Down LED Driver
List of Figures
List of Figures
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Total Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3 dB LED Current Deviation (12 V, 68 µH, 187 mΩ, 3 LEDs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Maximum LED Current Contrast Ratio (68 µH, 187 mΩ, 3 LEDs) . . . . . . . . . . . . . . . . . . . . . . . . . 18
Application Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
ILD4120 on Evaluation Board. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Package Outline (dimensions in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Recommended PCB Footprint for Reflow Soldering (dimensions in mm) . . . . . . . . . . . . . . . . . . . 28
Tape Loading (dimensions in mm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
BDTIC
Data Sheet
5
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ILD4120
1200 mA Step Down LED Driver
List of Tables
List of Tables
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Pin Definition and Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maximum Thermal Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Control Parameter at Pin PWM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switching Characteristics 12 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Switching Characteristics 24 V . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10
11
12
13
13
15
15
BDTIC
Data Sheet
6
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ILD4120
1200 mA Step Down LED Driver
List of Tables
BDTIC
Data Sheet
7
Revision 6.0, 2011-10-10
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1200 mA Step Down LED Driver with Internal Switch
ILD4120
1
•
•
•
•
•
•
•
•
•
•
•
•
•
Features
Wide input voltage range: 4.5 V ... 40 V
Internal switch for up to 1200 mA average LED current
Up to 95 % efficiency
Over current protection
Over voltage protection
Temperature protection mechanism
Inherent open-circuit LED protection
Soft-start capability
Low shut down current
Analog and PWM dimming possible
Typical 3 % output current accuracy
Minimum external components required
Package: DSO-8 with exposed pad
BDTIC
Applications
•
•
•
•
•
•
LED driver for general lighting applications
Retail, office and residential luminaires
Spot light / downlight
LED replacement lamps
Architectural lighting
Street lighting
Product Name
Package
Marking
ILD4120
DSO-8-27
ILD4120
Data Sheet
8
Revision 6.0, 2011-10-10
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ILD4120
1200 mA Step Down LED Driver
Product Brief
2
Product Brief
ILD4120 is a hysteretic step down LED driver IC for general lighting applications, which is capable to drive high
power LEDs with average currents up to 1200 mA.
The IC incorporates a wide input voltage range and an internal power switch. The output current level can be
adjusted with an external sense resistor.
The IC can be switched on and off by an external enable signal at the EN pin. The PWM pin is the input pin for
PWM and analog dimming of the LED current.
Depending on the value of the switching inductor the switching frequency and the voltage ripple can be set. The
precise internal bandgap stabilizes the circuit and provides stable current conditions over temperature range.
To ensure a long lifetime of the LED system the ILD4120 incorporates an overvoltage and an overcurrent
protection. In addition the integrated thermal protection will reduce the output current to protect the LEDs and the
IC against thermal stress.
BDTIC
ILD4120
Buck LED Controller
EN
1
8
VS
7
Vsense
6
Vswitch
5
Vswitch
Vstab
Over Voltage Protection
Vstab
PWM
I/V
2
Vstab
Vref
TPC
Vstab
GND
3
Vstab
Vstab
GND
Over Current Protection
4
EP
Figure 1
Data Sheet
ILD4120 _Block diagram.vsd
Block Diagram
9
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ILD4120
1200 mA Step Down LED Driver
Product Brief
Pin Definition
Table 1
Pin Definition and Function
Pin No.
Name
Pin
Type
Buffer
Type
Function
1
EN
Input
–
Chip enable signal
2
PWM
Input
–
Dimming signal:
• Analog dimming
• PWM dimming
3
GND
GND
–
IC ground
4
GND
GND
–
IC ground
Vswitch
Output
–
Power switch output
Vswitch
Output
–
Power switch output
Vsense
Input
–
LED current sense input
VS
Input
–
Supply voltage
Exposed Pad
GND
–
Heat spreader
5
6
7
8
BDTIC
EP
Data Sheet
10
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ILD4120
1200 mA Step Down LED Driver
Maximum Ratings
3
Maximum Ratings
Table 2
Maximum Ratings
Parameter
Symbol
Values
Min.
Typ.
Max.
Unit
Note /
Test Condition
Supply voltage
VS
–
–
45
V
–
Average output current
ISwitch
–
–
1200
mA
–
Total power dissipation, TS ≤ 120°C
Ptot
–
–
2000
mW
–
Junction temperature
TJ
–
–
150
°C
–
Storage temperature range
TSTG
-65
–
150
°C
–
ESD capability
at all pins
VESD HBM
kV
–
–
4
HBM acc. to
JESD22-A114
BDTIC
Attention: Stresses above the max. values listed here may cause permanent damage to the device.
Exposure to absolute maximum rating conditions for extended periods may affect device
reliability. Maximum ratings are absolute ratings; exceeding only one of these values may
cause irreversible damage to the integrated circuit.
Data Sheet
11
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ILD4120
1200 mA Step Down LED Driver
Thermal Characteristics
4
Thermal Characteristics
Table 3
Maximum Thermal Resistance
Parameter
Symbol
Values
Min.
Typ.
Unit
Max.
Note /
Test Condition
1)
Junction - soldering point
RthJS
–
–
15
K/W
–
1) For calculation of RthJA please refer to application note AN077 (Thermal Resistance Calculation)
2.5
BDTIC
Ptot [W]
2
1.5
1
0.5
0
Figure 2
Data Sheet
0
20
40
60
80
TS [°C]
100
120
140
160
Total Power Dissipation
12
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ILD4120
1200 mA Step Down LED Driver
Electrical Characteristics
5
Electrical Characteristics
5.1
DC Characteristics
All parameters at TA = 25 °C, unless otherwise specified.
VS = 12 V, VEN = 3 V, VPWM = 3 V
Table 4
DC Characteristics
Parameter
Symbol
Values
Min.
Unit
Typ.
Note / Test Condition
Max.
BDTIC
Operating supply voltage
VS
4.5
–
40
V
Overall current consumption open
load
IS open load
2.3
3.0
4.1
mA
VS = 4.5 V
ILED = 0 mA
Overall current consumption open
load
IS open load
2.3
3.2
4.2
mA
VS = 12 V
ILED = 0 mA
Overall current consumption open
load
IS open load
2.4
3.8
4.6
mA
VS = 40 V
ILED = 0 mA
Overall standby current consumption
IS standby
–
–
1
µA
VEN = 0 V
VS = 4.5..40 V
Enable voltage for standby mode
VEN, Off
-0.3
–
0.4
V
Enable voltage for operating mode
VEN, On
2.5
–
40
V
EN delay time
td, EN, On
–
3
–
µs
VPWM = 3 V
VEN = 0 V → 3 V
VSwitch = high → low
td, EN, Off
–
0.4
–
µs
VPWM = 3 V
VEN = 3 V → 0 V
VSwitch = low → high
Input current of enable pin
IEN
–
47
100
μA
VEN = 3 V
VS = 4.5..40 V
Current of sense input
Isense
–
20
–
μA
Vsense = 12 V
5.2
Analog and Digital Dimming Control
All parameters at TA = 25 °C, unless otherwise specified.
Table 5
Control Parameter at Pin PWM
Parameter
Symbol
Values
Unit
Min.
Typ.
Max.
PWM voltage logic low
VPWM. Low
-0.3
–
0.4
V
PWM voltage logic high
VPWM, High
2.5
–
40
V
PWM voltage for analog dimming
VPWM
1
–
2
Data Sheet
13
Note / Test Condition
full LED current
linear dimming range
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ILD4120
1200 mA Step Down LED Driver
Electrical Characteristics
Table 5
Control Parameter at Pin PWM
Parameter
Symbol
PWM delay time
Input current of PWM pin
Values
Unit
Note / Test Condition
Min.
Typ.
Max.
td, PWM, On
–
0.8
–
µs
VEN = 3 V
VPWM = 0 V → 3 V
VSwitch = high → low
td, PWM, Off
–
0.4
–
µs
VEN = 3 V
VPWM = 3 V → 0 V
VSwitch = low → high
IPWM
–
1.4
5
μA
VPWM = 3 V
BDTIC
Data Sheet
14
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ILD4120
1200 mA Step Down LED Driver
Electrical Characteristics
5.3
Switching Characteristics
All parameters at TA = 25 °C, unless otherwise specified.
VS = 12 V, 3 LEDs, VfLED = 3 V, Rsense = 187 mΩ (ILED = 625 mA), L = 68 μH, VEN = 3 V, VPWM = 3 V
Table 6
Switching Characteristics 12 V
Parameter
Symbol
Values
Unit
Min.
Typ.
Max.
Note / Test Condition
Switching frequency
fSwitch
–
77
–
kHz
Maximum switching frequency
fSwitch max
–
–
500
kHz
for any coil value
–
117
–
mV
voltage offset below VS
Mean current sense threshold voltage Vsense
BDTIC
Vsensehys
–
±14
–
%
Residual voltage at collector of power Vswitch on
transistor
–
0.92
–
V
Output current accuracy
Ioutacc
–
±3
–
%
Over temperature protection
TS, TSD
–
106
–
°C
Sense threshold hysteresis
output switch turned on
TS for 10 % ILED
reduction, defined by TJ
VS = 24 V, 6 LEDs, VfLED = 3 V, Rsense = 100 mΩ (ILED = 1070 mA), L = 47 μH, VEN = 3 V, VPWM = 3 V
Table 7
Switching Characteristics 24 V
Parameter
Symbol
Values
Unit
Min.
Typ.
Max.
Note / Test Condition
Switching frequency
fSwitch
–
110
–
kHz
Maximum switching frequency
fSwitch max
–
–
500
kHz
for any coil value
Mean current sense threshold voltage Vsense
–
107
–
mV
voltage offset below VS
Sense threshold hysteresis
Vsensehys
–
±22
–
%
Residual voltage at collector of power Vswitch on
transistor
–
1.03
–
V
Output current accuracy
Ioutacc
–
±3
–
%
Over temperature protection
TS, TSD
–
87
–
°C
Data Sheet
15
output switch turned on
TS for 10 % ILED
reduction, defined by TJ
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
6
Basic Application Information
This section covers the basic information required for calculating the parameters for a certain LED application. For
detailed application information please check Application Note AN270 (Driving 2 W LEDs with ILD4120) or visit
our web site http://www.infineon.com/led.appnotes
6.1
Setting the average LED current
The average output current for the LEDs is set by the external sense resistor Rsense. To calculate the value of this
resistor a first approximation can be calculated using Equation (1).
Vsense is dependent on the supply voltage VS and the number of LEDs in series.
Rsense =
Vsense
I LED
BDTIC
(1)
Example calculation 1
VS = 12 V, L = 68 µH, VfLED = 3 V, 3 LEDs in series
→ Vsense = 117 mV
ILED = 625 mA
→ Rsense = 187 mΩ
Example calculation 2
VS = 24 V, L = 47 µH, VfLED = 3 V, 6 LEDs in series
→ Vsense = 107 mV
ILED = 1070 mA
→ Rsense = 100 mΩ
An easy way to achieve these resistor values is to connect standard resistors in parallel.
6.2
Dimming of the LEDs
Analog voltage dimming
The PWM pin can be used for analog dimming of the LED current applying an analog control voltage. To achieve
a linear change in LED current versus control voltage the recommended voltage range is 1 V to 2 V. The maximum
achievable LED current is defined by resistor Rsense. The maximum LED current will be achieved for VPWM ≥ 2.5 V.
Data Sheet
16
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
ILED versus VPWM, TA=25 °C
1.1
110
187 mΩ, 68 μH
100 mΩ, 47 μH
1
0.9
187 mΩ, 68 μH
100 mΩ, 47 μH
100
90
0.8
80
0.7
70
ILED [%]
ILED [A]
ILED (relative) versus VPWM, TA=25 °C
0.6
0.5
0.4
60
50
40
0.3
30
0.2
20
0.1
10
BDTIC
0
0
0.5
1
1.5
VPWM [V]
2
2.5
ILED versus VPWM, Rsense = 187 mΩ, L = 68 µH
0.7
0.5
110
0.5
1
1.5
VPWM [V]
2
2.5
3
TA = -40 °C
TA = 25 °C
TA = 85 °C
TA = 105 °C
100
90
80
ILED [%]
0.4
0.3
0.2
70
60
50
40
30
20
0.1
0
0
ILED (relative) vs. VPWM, Rsense = 187 mΩ, L = 68 µH
TA = -40 °C
TA = 25 °C
TA = 85 °C
TA = 105 °C
0.6
ILED [A]
0
3
10
0
0.5
1
1.5
VPWM [V]
2
2.5
0
3
0
0.5
1
1.5
VPWM [V]
2
2.5
3
PWM Dimming
Besides the analog dimming functionality the PWM pin acts as the input for a pulse width modulated (PWM) signal
to control the dimming of the LED current.
The achievable dimming ratio of the LED current depends mainly on the rise and fall time of the LED current and
is thus dependent on supply voltage, LED string forward voltage and inductance value. Due to rise / fall times the
LED current will be lower than PWM duty cycle and difference increases the lower PWM duty cycle becomes.
Figure 3 shows the PWM duty cycle at which average LED current is 3 dB lower than PWM duty cycle. As an
example the average LED current will be 3 dB lower at 280 Hz PWM frequency and 1:100 duty cycle.
Data Sheet
17
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
PWM Duty Cycle [1:]
1000
100
BDTIC
10
1
100
1000
10000
PWM Frequency [Hz]
Figure 3
3 dB LED Current Deviation (12 V, 68 µH, 187 mΩ, 3 LEDs)
As shown in Figure 4 higher LED current contrast ratios can be still achieved if higher deviations between PWM
duty cycle and LED current ratio are accepted.
LED Current Contrast Ratio [1:]
10000
1000
100
10
1
100
Figure 4
Data Sheet
VS = 40 V
VS = 30 V
VS = 20 V
VS = 15 V
VS = 12 V
1000
10000
PWM Frequency [Hz]
Maximum LED Current Contrast Ratio (68 µH, 187 mΩ, 3 LEDs)
18
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
6.3
Temperature Protection Circuit
ILD4120 incorporates a temperature protection circuit referring to the junction temperature of ILD4120. The higher
the junction temperature of ILD4120 the lower the current of the LEDs. This feature helps to reduce the power
dissipation of ILD4120 and the LEDs. Yet still the product specific maximum ratings for junction temperature need
to be observed to avoid a permanent damage of the devices.
ILD4120 has been characterized on ILD4120 application board heated from the backside without additional air
flow on the circuit board surface besides natural convection. Design and layout of the circuit board as well as the
air flow influence the thermal resistance junction to ambient RthJA of ILD4120 and thus its junction temperature.
Below figures show the LED current versus soldering point temperature TS.
ILED versus TS, VS = 12 V, Rsense = 187 mΩ
ILED (relative) versus TS, VS = 12 V, Rsense = 187 mΩ
BDTIC
0.7
110
100
0.6
90
ILED [%]
ILED [A]
0.5
0.4
0.3
80
70
60
50
0.2
0.1
40
50
60
70
80
90
TS [°C ]
100
110
120
30
130
50
187 mΩ, 100 μH
187 mΩ, 47 μH
187 mΩ, 68 μH
60
70
80
100
110
120
130
187 mΩ, 100 μH
187 mΩ, 47 μH
187 mΩ, 68 μH
ILED versus TS, VS = 24 V, Rsense = 187 mΩ
90
TS [°C ]
ILED (relative) versus TS, VS = 24 V, Rsense = 187 mΩ
0.7
110
100
0.6
90
ILED [%]
ILED [A]
0.5
0.4
0.3
80
70
60
50
0.2
0.1
40
50
60
70
187 mΩ, 47 μH
187 mΩ, 68 μH
Data Sheet
80
90
TS [°C ]
100
110
120
30
130
187 mΩ, 100 μH
50
60
70
187 mΩ, 47 μH
187 mΩ, 68 μH
19
80
90
TS [°C ]
100
110
120
130
187 mΩ, 100 μH
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
ILED versus TS, VS = 12 V, Rsense = 100 mΩ
ILED (relative) versus TS, VS = 24 V, Rsense = 100 mΩ
1.3
110
1.2
100
1.1
90
0.9
ILED [%]
ILED [A]
1
0.8
0.7
0.6
80
70
60
50
0.5
40
BDTIC
0.4
0.3
50
60
70
80
100 mΩ, 22 μH
100 mΩ, 33 μH
90
TS [°C ]
100
110
120
30
130
70
80
90
TS [°C ]
100
110
120
130
100 mΩ, 47 μH
ILED (relative) versus TS, VS = 24 V, Rsense = 100 mΩ
1.3
110
1.2
100
1.1
90
1
0.9
ILED [%]
ILED [A]
60
100 mΩ, 22 μH
100 mΩ, 33 μH
100 mΩ, 47 μH
ILED versus TS, VS = 24 V, Rsense = 100 mΩ
0.8
0.7
0.6
80
70
60
50
0.5
40
0.4
0.3
50
50
60
70
80
100 mΩ, 22 μH
100 mΩ, 33 μH
6.4
90
TS [°C ]
100
110
120
30
130
100 mΩ, 47 μH
50
60
70
100 mΩ, 22 μH
100 mΩ, 33 μH
80
90
TS [°C ]
100
110
120
130
100 mΩ, 47 μH
Switching Parameters
For all shown parameters ILD4120 has been measured on evaluation board ILD4120 at TA = 25 °C. Used LEDs
have a typical forward voltage VfLED of 3 V. For details see Application Note AN270 (Driving 2 W LEDs with
ILD4120) or visit our web site http://www.infineon.com/lowcostleddrivers.
Data Sheet
20
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 187 mΩ, L= 47 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
0.8
500
0.75
400
fSwitch [kHz]
ILED [A]
0.7
0.65
0.6
300
200
BDTIC
100
0.55
0.5
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
21
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 187 mΩ, L= 68 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
0.8
500
0.75
400
fSwitch [kHz]
ILED [A]
0.7
0.65
0.6
300
200
BDTIC
100
0.55
0.5
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
22
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
Revision 6.0, 2011-10-10
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 187 mΩ, L= 100 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
0.8
500
0.75
400
fSwitch [kHz]
ILED [A]
0.7
0.65
0.6
300
200
BDTIC
100
0.55
0.5
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
23
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 100 mΩ, L= 22 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
1.5
500
1.4
400
fSwitch [kHz]
ILED [A]
1.3
1.2
1.1
300
200
1
BDTIC
100
0.9
0.8
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
24
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
Revision 6.0, 2011-10-10
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 100 mΩ, L= 33 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
1.5
500
1.4
400
fSwitch [kHz]
ILED [A]
1.3
1.2
1.1
300
200
1
BDTIC
100
0.9
0.8
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
25
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
Revision 6.0, 2011-10-10
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ILD4120
1200 mA Step Down LED Driver
Basic Application Information
Rsense = 100 mΩ, L= 47 µH
ILED versus VS and Number of LEDs
fSwitch versus VS and Number of LEDs
1.5
500
1.4
400
fSwitch [kHz]
ILED [A]
1.3
1.2
1.1
300
200
1
BDTIC
100
0.9
0.8
0
5
10
15
20
25
VS [V]
3 LEDs
4 LEDs
1 LED
2 LEDs
30
35
40
0
45
0
5 LEDs
6 LEDs
5
10
15
3 LEDs
4 LEDs
1 LED
2 LEDs
Efficiency versus VS and Number of LEDs
20
25
VS [V]
30
35
40
45
40
45
5 LEDs
6 LEDs
Duty Cycle versus VS and Number of LEDs
100
100
95
80
Duty Cycle [%]
Efficiency [%]
90
85
80
75
70
60
40
20
65
60
0
5
10
1 LED
2 LEDs
Data Sheet
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
40
0
45
5 LEDs
6 LEDs
0
5
10
1 LED
2 LEDs
26
15
20
25
VS [V]
3 LEDs
4 LEDs
30
35
5 LEDs
6 LEDs
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ILD4120
1200 mA Step Down LED Driver
Application Circuit
7
Application Circuit
Vs
EN
1
8
V s tab
BDTIC
Rs ens e
OV P
PWM
V ref
I/V
2
V s tab
7
Vref
TPC
V s tab
3
V s tab
6
V s tab
OCP
4
EP
5
Exposed pad to be connected to GND
ILD4120 _Application circuit.vsd
Figure 5
Application Circuit
8
Evaluation Board
Figure 6
Data Sheet
ILD4120 on Evaluation Board
27
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ILD4120
1200 mA Step Down LED Driver
Package Information
9
Package Information
0.35 x 45˚
1.27
0.41±0.09 2)
0.1 C D 2x
0.08 C
Seating Plane
C
8˚ MAX.
0.19 +0.06
1.7 MAX.
Stand Off
(1.45)
0.1+0
-0.1
3.9 ±0.11)
0.64 ±0.25
BDTIC
0.2
M
C A-B D 8x
D
0.2
6 ±0.2
M
D 8x
Bottom View
8
1
5
1
4
8
4
5
2.65 ±0.2
3 ±0.2
A
B
4.9 ±0.11)
0.1 C A-B 2x
Index Marking
1) Does not include plastic or metal protrusion of 0.15 max. per side
2) Dambar protrusion shall be maximum 0.1 mm total in excess of lead width
3) JEDEC reference MS-012 variation BA
Figure 7
PG-DSO-8-27-PO V01
Package Outline (dimensions in mm)
1.31
0.65
3
1.27
2.65
5.69
PG-DSO-8-27-FP V01
Recommended PCB Footprint for Reflow Soldering (dimensions in mm)
0.3
8
5.2
Pin 1 marking
6.4
12 ±0.3
Figure 8
1.75
2.1
PG-DSO-8-27-TP V05
Figure 9
Data Sheet
Tape Loading (dimensions in mm)
28
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BDTIC
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Published by Infineon Technologies AG
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