Infineon Technologies BCR401RE6433HTMA1

Overview

BCR401RE6433HTMA1 from Infineon Technologies is a constant-current linear LED driver in SOT143R package, delivering 10 mA nominal output with external resistor adjustment up to 60 mA, 1.2 V minimum supply overhead, and -0.3 %/K negative thermal coefficient for LED lifetime protection. It operates up to 18 V supply and is qualified per AEC-Q101 for automotive interior lighting.

For engineers reviewing the BCR401RE6433HTMA1 datasheet, BCR401RE6433HTMA1 pinout, BCR401RE6433HTMA1 application, or BCR401RE6433HTMA1 equivalent, key selection criteria include thermal derating behavior, external current-setting resistor calculation, low-voltage-drop operation at 1.2 V, and AEC-Q101 qualification for harsh-environment lighting.

Technical Context

The BCR401RE6433HTMA1 implements a monolithic bipolar transistor-based constant-current source with internal 79 Ω reference resistor (typ), enabling precise current regulation independent of LED forward voltage variation and supply ripple. Its architecture integrates thermal sensing to reduce output current linearly with junction temperature rise.

It supports parallel operation for higher current without external ballasting resistors and allows dimming via ground-pin modulation using an external digital transistor. Operation above 18 V is enabled by relocating LEDs between VS and driver supply pin, shifting voltage stress away from the IC.

Key Specifications

Pinout & Package

SOT143R is a 4-pin plastic surface-mount package with exposed thermal pad (pin 3 = VS serves as primary thermal path). Dimensions: 2.4 mm × 1.3 mm × 0.9 mm, pitch 0.95 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with BCR401RE6433HTMA1, the BCR402R offers integration density at higher static power, while the NSIC2020B trades adjustability and thermal protection for tighter initial accuracy and lower BOM count in fixed-current systems.

Availability

BCR401RE6433HTMA1 is available at Aetrix Electronics and suitable for channel-letter signage, aircraft cabin lighting, and refrigerator interior illumination requiring stable component supply, AEC-Q101 compliance, and thermal-aware current regulation.

Supply support for BCR401RE6433HTMA1 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies AG is a German semiconductor manufacturer specializing in power management, automotive electronics, and industrial control ICs.

The BCR401R belongs to Infineon's low-cost linear LED driver product line, designed specifically for reliable, EMI-free illumination in cost-sensitive automotive, appliance, and architectural lighting applications.

FAQ

What is the maximum number of BCR401RE6433HTMA1 drivers that can be safely paralleled?

Up to four units may be paralleled without external balancing, provided PCB layout ensures matched thermal coupling and trace impedance. Parallel operation relies on inherent current-matching due to monolithic process matching and shared thermal environment-exceeding four units risks thermal runaway if local heating diverges beyond ±5°C.

How is the external resistor Rext calculated for a target output current?

Rext is derived from the equation Rext = Vdrop / (Iout − Vdrop/Rint), where Vdrop ≈ 0.79 V at 20 mA (per datasheet), and Rint = 79 Ω (typ). For 30 mA output, Vdrop ≈ 0.85 V → Rext ≈ 0.85 V / (0.03 A − 0.85 V / 79 Ω) ≈ 32.5 Ω. Use standard 1% E96 values and verify with thermal derating.

Does BCR401RE6433HTMA1 support analog dimming?

No-only digital (PWM) dimming is supported via the GND pin. An external NPN transistor switches the ground path at frequencies ≥200 Hz to avoid visible flicker. Analog dimming would require modulating the Rext node, which is not specified or characterized for dynamic operation and risks instability.

Can BCR401RE6433HTMA1 drive LEDs with total forward voltage exceeding 18 V?

Yes-by reconfiguring the LED string between VS and the driver's VS pin (not Iout), the IC regulates current while the full LED string voltage appears across the supply rail. This "high-side" configuration shifts voltage stress from the IC to the power supply, enabling operation with 24 V or higher rails while keeping VS ≤18 V across the device.