Infineon Technologies TLE4476D

Overview

TLE4476D from Infineon Technologies is a dual low-dropout linear voltage regulator IC designed for automotive microprocessor power supply, delivering 3.3 V @ 350 mA and 5.0 V @ 430 mA with ±4% output accuracy, reverse battery protection up to −42 V, and AEC-Q100 qualification for under-hood use.

For engineers reviewing the TLE4476D datasheet, TLE4476D pinout, TLE4476D application, or TLE4476D equivalent, this device supports critical dual-rail MCU power sequencing, enables selective 5 V rail shutdown via EN input, and meets stringent automotive thermal (−40 °C to 170 °C) and overvoltage (65 V transient) requirements.

Technical Context

The TLE4476D integrates two independent LDO regulators on a single monolithic die: Q1 (3.3 V) operates down to 4.5 V input, while Q2 (5.0 V) requires ≥5.7 V input and features an active-high enable input (EN) referenced to GND. Both outputs include internal current limiting, thermal shutdown, and short-circuit protection.

Its architecture incorporates bandgap reference-based error amplifiers, reverse-battery protection diodes, and overvoltage clamping circuitry rated for 65 V transients (<400 ms). The device uses PG-TO252-5-11 package with exposed thermal pad for junction-to-case thermal resistance of 3 K/W.

Key Specifications

Pinout & Package

Package: PG-TO252-5-11 (D-Pak) with exposed thermal pad; thermally optimized for PCB mounting on 300 mm² copper area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-output automotive LDO regulator applications.

Compared with TLV70733PDPKR and TPS7B8750QKVURQ1, the TLE4476D uniquely delivers both regulated rails in one AEC-Q100-qualified device with reverse-battery and 65 V transient protection-reducing BOM count and PCB area in dual-voltage automotive ECUs.

Availability

TLE4476D is available at Aetrix Electronics and suitable for engine control units, body control modules, and transmission control units requiring stable component supply across extended automotive temperature and voltage stress conditions.

Supply support for TLE4476D 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 is a German semiconductor manufacturer specializing in power management, automotive ICs, and industrial control solutions.

The TLE4476D belongs to Infineon's TLE automotive linear regulator product line, engineered specifically for robust dual-rail power delivery in engine bay and chassis-mounted electronic control units.

FAQ

What is the minimum input voltage required to regulate both outputs?

The TLE4476D requires ≥4.5 V input to regulate Q1 (3.3 V) and ≥5.7 V to regulate Q2 (5.0 V). Below these thresholds, the respective output drops out of regulation. Both rails remain functional down to 4.5 V if only Q1 is needed, but Q2 will not regulate until VI exceeds 5.7 V.

Can the EN pin be left unconnected or pulled to GND?

No. Leaving EN floating risks undefined Q2 state due to noise susceptibility. Pulling EN to GND forces Q2 OFF permanently. For guaranteed Q2 operation, EN must be actively driven high (>1.8 V) via battery (terminal 30), ignition (terminal 15), or MCU GPIO with appropriate voltage translation if needed.

Does the TLE4476D require external capacitors, and what are their critical values?

Yes: C_I (input) ≥1 μF ceramic is mandatory for stability; C_Q1 ≥10 μF with ESR <2 Ω at 10 kHz; C_Q2 ≥10 μF with ESR <3 Ω at 10 kHz. Using lower capacitance or higher ESR risks oscillation or poor transient response, especially during load steps.

How does overtemperature protection behave during sustained 170 °C operation?

Overtemperature protection triggers above 170 °C junction temperature, shutting down both outputs. However, continuous operation at 170 °C reduces statistical lifetime to ~500 hours. The device is rated for 170 °C maximum, not continuous operation-designs must ensure thermal design keeps T_j <150 °C under worst-case load and ambient.