ILD4035 Infineon Technologies, ILD4035 Datasheet - Page 16

• Manufacturer Part Number: ILD4035
• Manufacturer: Infineon Technologies
• Type: Buckr

Specifications of ILD4035

• Packages: SC74
• Vs (min): 4.5 V
• Vs (max): 40.0 V
• Iout (typ): 350.0 mA
• Iout (max): 400.0 mA

6
This section covers the basic information required for calculating the parameters for a certain LED application.
For detailed application information please check the Application Note AN215 (Driving 1 W LEDs with ILD4035)
or visit our web site http://www.infineon.com/led.appnotes
6.1
The average output current for the LEDs is set by the external sense resistor
resistor a first approximation can be calculated using
V
Example calculation 1
V
→
I
→
Example calculation 2
V
→
I
→
An easy way to achieve these resistor values is to connect standard resistors in parallel
6.2
Analog voltage dimming
The voltage level of the EN/PWM pin can be used for analog dimming of the LED current. To achieve a linear
change in LED current versus control voltage the recommended voltage range at the EN/PWM pin is 1 V to 2 V.
The maximum achievable LED current is defined by resistor
V
performance is shown in below figures.
LED
LED
R
Data Sheet
sense
S
S
EN
sense
V
R
V
R
= 12 V, 100 µH,
= 24 V, 100 µH,
sense
sense
sense
sense
≥ 2.5 V. Below 0.4 V the ILD4035 is set to standby mode and the output is switched off. The typical dimming
= 375 mA
= 350 mA
is dependent on the supply voltage
=
V
= 114 mV
= 303 mΩ
= 106 mV
= 303 mΩ
I
sense
LED
Basic Application Information
Setting the average LED current
Dimming of the LEDs
V
V
fLED
fLED
= 3 V, 3 LEDs in series
= 3 V, 6 LEDs in series
V
S
and the number of LEDs in series.
Equation
16
R
sense
(2).
. The maximum LED current will be achieved for
350 mA Step Down LED Driver
R
sense
Basic Application Information
. To calculate the value of this
Revision 2.0, 2011-08-17
ILD4035
(2)