BCR450 - High precision controller for high brightness LEDs

Ikrumm — Thu, 07 Oct 2021 03:51:22 GMT

Current Revision posted to Documents by Ikrumm on 10/7/2021 3:51:22 AM

Due to the enormous successes in recent years in getting out more lumen per watt, LEDs are starting to penetrate more and more illumination applications with high brightness LEDs. LEDs starting from 0.5W with drive currents between 150 to 200mA going up to several watts with drive currents of 700mA belong to the category of high brightness LEDs.

Infineon Technologies has recently issued the application note AN101 for high current applications with an unbeatable cost position for LED drivers. The AN101 based on a low cost BCR 401R in combination with a booster transistor is addressing high current applications which don’t require any frills and fancy features.

The new BCR 450 follows the same concept as described in AN101 that combines an LED Controller with an external power stage with the difference that the BCR 450 contains some more useful features than BCR 401R used in AN101. The combination of the external power stage next to an intelligent and feature-rich IC like the BCR450 is the most cost efficient solution in the industry besides the advantage of spreading the heat dissipation over two devices instead of one monolithic driver IC.

Infineon PN

BCR450

Features

Linear mode driver
High precision current control +/- 1.6% at 25°C
Stand alone: 10mA – 85mA (adjustable with external resistor)
Booster circuit: 85mA – 5A
Maximum power dissipation of booster transistor, in case of BCX68-25 - 1.5W,
but higher power dissipation possible by usage of other booster transistors
Over voltage protection up to 45V , maximum operating voltage 27V
Thermal shutdown-protection for LEDs
Low voltage overhead of 0.45V in boost operation
Logic levels enable input, direct PWM dimmable

Applications

High precision lighting applications
Architectural and landscape lighting
Aircraft lighting
Interior/exterior building lighting
Advertising panels
Light bars on emergency vehicles
EM I sensitive lighting applications
Other types of general lighting applications

Benefits

No EM I problems
Differences in brightness resulting from temperature variation can be avoided
External power stage allows improved heat dissipation in comparison to monolithic drivers
Thermal shutdown function ensures that the LED Driver and the LEDs are protected
Higher count of LEDs in a string due to very low voltage overhead
Low part count, no external digital transistor or coils required
Excellent price-performance-ratio, due to separation of power-stage from higher cost IC technology

Datasheet

BCR450

Application note

AN066 - BCR402R: Light Emitting Diode (LED) Driver IC Provides Constant LED Current Independent of Supply Voltage Variation

AN097 - Using BCR402R/BCR402U at High Supply Voltages

AN101 - Using Infineon‘s BCR400 Family of Constant-Current, Linear-Mode LED Drivers for Lighting Applications from 10 mA - 700 mA

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