Infineon Technologies TLE42644G

Overview

TLE42644G from Infineon Technologies is a monolithic low-dropout linear voltage regulator delivering a fixed 5 V output with ±2% accuracy up to 50 mA and ±3% up to 100 mA, featuring 40 µA typical quiescent current, reverse polarity protection, and overtemperature shutdown. It operates across -40°C to +150°C and supports input voltages from 5.5 V to 40 V, making it suitable for always-on automotive subsystems such as body control modules and sensor interfaces.

For engineers reviewing the TLE42644G datasheet, TLE42644G pinout, TLE42644G application, or TLE42644G equivalent, key selection criteria include dropout voltage (220 mV typ. at 100 mA), thermal resistance (R_thJA = 54 K/W on FR4 2s2p), AEC-Q100 qualification, PG-SOT223-4 package compatibility, and 150–500 mA current limiting behavior under fault conditions.

Technical Context

The TLE42644G integrates bandgap reference, error amplifier, saturation control, and thermal shutdown circuitry in a single die. Its architecture enables stable regulation with ceramic output capacitors ≥10 µF and ESR ≤2 Ω at 10 kHz, while internal current limiting and reverse-polarity protection operate without external components.

It uses a PMOS pass transistor topology enabling ultra-low dropout and minimal quiescent current drift over temperature. The device enters thermal shutdown at 151–200°C with 25°C hysteresis, and maintains output regulation down to input voltages as low as 5.5 V - critical for cold-crank automotive battery scenarios.

Key Specifications

Pinout & Package

Package: PG-SOT223-4 - surface-mount, thermally enhanced with exposed heat slug internally connected to GND. Requires PCB copper pour under slug for effective heat dissipation (R_thJC = 17 K/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-quiescent-current automotive LDO applications.

Compared with TLE4264G and TLV73350PDBVR, the TLE42644G uniquely combines AEC-Q100 Grade 0 qualification, 40 µA I_Q, reverse polarity protection, and 40 V input capability - making it the sole choice for safety-critical, always-on automotive 5 V regulation.

Availability

TLE42644G is available at Aetrix Electronics and suitable for body control modules, occupant detection systems, engine sensor interfaces, and adaptive lighting control units requiring stable component supply across extended automotive lifecycles.

Supply support for TLE42644G 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, with global manufacturing and qualification infrastructure.

The OPTIREG™ linear product line delivers AEC-Q100-qualified voltage regulators optimized for harsh automotive environments - emphasizing ultra-low I_Q, wide input range, and integrated protection for always-on electronic control units.

FAQ

What is the minimum input voltage required for regulation at 100 mA load?

The TLE42644G maintains regulation down to 5.5 V input across its full operating temperature range. At 100 mA load and 25°C, the dropout voltage is 220 mV typ., so regulation begins at approximately 5.22 V - but the functional minimum specified in datasheet Table 2 is 5.5 V to ensure stability and margin across all conditions including ESR variation and temperature extremes.

Can the TLE42644G replace the TLE4264-2G without PCB changes?

Yes - the TLE42644G is explicitly stated as a 1-to-1 replacement for TLE4264-2G and is pin compatible in the PG-SOT223-4 package. Both share identical pin assignment (I-GND-Q-GND), thermal slug connection, and footprint. No layout modification is needed, though system-level validation of reduced quiescent current impact on upstream power sequencing is recommended.

Does the device require an input capacitor, and what value is recommended?

Yes - a low-ESR ceramic input capacitor (≥1 µF, X7R or better) placed as close as possible to the I and GND pins is required to suppress high-frequency noise and prevent oscillation. While not explicitly specified in the "Functional Range" table, Infineon's application guidance and layout examples consistently show ≥1 µF ceramic input capacitance for stability under fast load transients and EMI immunity.

How does the overtemperature shutdown behave during sustained overload?

The TLE42644G activates thermal shutdown at 151–200°C junction temperature and remains latched off until junction cools by at least 25°C hysteresis. During sustained overload, it cycles between regulation and shutdown - not continuous current limiting - to prevent permanent damage. This behavior is intentional per datasheet Note 2: protection functions are not designed for repetitive continuous operation.