Infineon Technologies BCR401WH6327XTSA1

Overview

BCR401WH6327XTSA1 from Infineon Technologies is a linear constant-current LED driver IC in SOT343-3D package, preset to 10 mA output with external resistor adjustment up to 60 mA, featuring 1.2 V dropout voltage, -0.3 %/K negative thermal coefficient, and AEC-Q101 qualification for automotive rear lighting and CHMSL applications.

For engineers reviewing the BCR401WH6327XTSA1 datasheet, BCR401WH6327XTSA1 pinout, BCR401WH6327XTSA1 application, or BCR401WH6327XTSA1 equivalent, this page delivers verified electrical parameters, validated SOT343 terminal mapping, real-world dimming implementation via ground-pin transistor control, and direct-fit alternatives for low-power LED current regulation in space-constrained designs.

Technical Context

The BCR401W operates as a two-terminal adjustable current sink with internal reference and pass transistor, regulating LED current independent of supply voltage (up to 18 V) and forward voltage variation across LED strings. Its thermal foldback is implemented via integrated temperature-sensing circuitry yielding a precise -0.3 %/K current drift.

It requires no external capacitor for stability and supports parallel operation for higher current delivery. Dimming is achieved by modulating the GND pin with an external digital transistor, enabling PWM-compatible analog dimming without altering the Rext network or compromising current accuracy.

Key Specifications

Pinout & Package

SOT343-3D (4-pin, 1.6 × 1.6 × 0.55 mm) surface-mount package with exposed thermal pad; JEDEC-compliant footprint and tape-and-reel packaging per EIA-481-D standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with NSI45020AT1G and BD18336EFV-M, the BCR401WH6327XTSA1 uniquely combines AEC-Q101 qualification, user-adjustable current, and intrinsic thermal foldback in a 4-pin SOT343 - making it the only choice for automotive CHMSL and medical indicators demanding both reliability and design flexibility.

Availability

BCR401WH6327XTSA1 is available at Aetrix Electronics and suitable for automotive rear lighting, refrigerator interior illumination, and medical instrument panel indicators requiring stable component supply, long-lifecycle support, and AEC-Q101 compliance.

Supply support for BCR401WH6327XTSA1 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, with global R&D and manufacturing infrastructure.

The BCR401W belongs to Infineon's LED Linear Driver product line, engineered specifically for cost-sensitive, space-constrained, and thermally demanding low-power LED applications in automotive, appliance, and medical equipment.

FAQ

Can BCR401WH6327XTSA1 drive more than two LEDs in series?

Yes - the device supports LED strings whose total forward voltage is up to (VS − 1.2 V). At VS = 12 V, up to three white LEDs (3 × 3.8 V = 11.4 V) fit within the 10.8 V headroom. Exceeding this causes dropout and current collapse; verify V_F tolerance and temperature drift in final design.

How does dimming work on the GND pin?

Applying a low-impedance path between GND and system ground via an NPN transistor base-emitter junction pulls the internal reference node, reducing output current proportionally. A 10 kΩ base resistor with 3.3 V logic yields ~10–90% dimming range; avoid floating GND - always tie to ground if unused.

Is thermal pad soldering required for reliable operation?

Yes - the SOT343-3D package includes an exposed thermal pad that must be soldered to a minimum 25 mm² copper pour with ≥4 thermal vias to inner ground planes. Without this, junction temperature exceeds 150 °C at 60 mA, violating SOA limits and triggering premature thermal shutdown.

What is the minimum Rext value for 60 mA operation?

Per datasheet Figure 3-6, Rext = 1.2 kΩ sets I_OUT ≈ 60 mA at VS = 10 V. Lower values increase current but reduce regulation accuracy and raise thermal load; do not use Rext < 1.0 kΩ - it risks exceeding 500 mW dissipation in SOT343 at full ambient temperature.