InfineonILD4001高效5WLED驅(qū)動方案

Infineon公司的ILD4001是用來驅(qū)動大功率LED室內(nèi)外照明的滯后的降壓LED控制器，其內(nèi)部的推挽輸出級能驅(qū)動外接N溝MOSFET功率晶體管，LED的電流在350mA到3A,效率高達98%?？刂破鬏斎腚妷?.5V-42V，開關(guān)頻率高達500kHz，模擬和PWM調(diào)光，輸出電流精度3%，LED電流的溫度漂移非常低，主要用于LED室內(nèi)外照明，建筑物照明和MR16等LED替代燈以及家用電器等。本文介紹了ILD4001主要特性，方框圖，典型應(yīng)用電路圖以及評估板主要指標，電路圖和材料清單。

The ILD4001 is a hysteretic buck LED controller IC for driving high power LEDs in indoor and outdoor lighting applications.

The LED controller is capable of driving an external MOSFET power transistor with the internal push-pull output stage to achieve LED currents of 350 mA up to 3 A and more depending on the dimensioning of the MOSFET, the thermal budget of the circuit board and the current sense resistor.

The ILD4001 is widely suitable for LED applications with supply voltages up to 42 V. A multifunctional enable pin allows dimming of the LEDs with DC voltage or a PWM signal. Furthermore the enable pin can be used to switch the LED controller on and off to minimize power consumption in standby.

The ILD4001 incorporates an integrated thermal shutdown function pulling low the Vdrive output signal once the junction temperature exceeds the threshold temperature. Once the junction temperature drops below the threshold temperature the Vdrive output is activated again.

To provide maximum design flexibility, the ILD4001 is housed in a small SC-74 package.

ILD4001主要特性：

? Wide input voltage range: 4.5 V ... 42 V

? Capable to drive N-channel MOSFETs that provide up to 3 A output current and up to 98% efficiency

? Temperature shut down mechanism

? Switching frequency up to 500 kHz

? Analog and PWM dimming possible

? Typical 3 % output current accuracy

? Very low LED current drift over temperature

? Minimum external component required

? Small package: SC-74

ILD4001應(yīng)用：

? LED controller for indoor and outdoor illumination

? LED replacement lamps, e.g. MR16 halogen replacement

? Retail, office and residential high power luminaires

? Architectural lighting

? Downlights and light engines

? Appliances, e.g. fridge / freezer


圖1。ILD4001方框圖

圖2。ILD4001應(yīng)用電路圖

圖3。ILD4001采用BSP318S的評估板外形圖

This document contains information about the LED-Less Demonstration Board for ILD4001. Please refer to the datasheet for the pins descriptions, functions descriptions and specifications.

The ILD4001 is a hysteretic buck LED controller IC for industrial applications.

The LED Controller is capable to drive external bipolar or MOSFET power transistors by using the internal push-pull output stage.

ILD4001 maintains a constant current through a string of LEDs as long as the input voltage exceeds the sum of the forward voltages of the LEDs in the string by at least 3V. The maximum input voltage for this demonstration board must not exceed 30V due to the board is optimizing for the 30V operation. If there is a need to test the board with a maximum supply voltage of 42V, please replace the schottky diode SD1 and the external MOSFET T1 with a suitable breakdown voltage.

The precise internal bandgap stabilizes the circuit and provides stable current conditions over temperature range.

Furthermore, temperature shut down mechanism enforce the IC to protect attached LEDs.

The board includes an “EN/PWM” input terminal for digital or analog dimming control signal.

The demonstration board is designed to operate at ambient temperatures up to 100?C. Although a wide variety of LED combinations and currents can be driven with the ILD4001, the sense-resistors have to be altered to achieve the desire LED current and inductance has to be changed to attain recommended switching frequencies below 500 kHz.

ILD4001評估板主要指標：


圖4。評估板電路圖
評估板材料清單：

詳情請見：
http://www.infineon.com/dgdl/ILD4001-Step-down-LED-Controller-Rev2.0.pdf?folderId=db3a30431f848401011fcbf2ab4c04c4fileId=db3a30433072cd8f01308fc1af03786b
和
http://www.infineon.com/dgdl/AN213.pdf?folderId=db3a304313b8b5a60113d4239297042ffileId=db3a304330dd34290130e5572ce63ea5