STMicroelectronics EV-AUTO-LDOS

Overview

EV-AUTO-LDOS from STMicroelectronics is an AEC-Q100 qualified automotive 5 V, 500 mA low-dropout linear regulator with integrated watchdog timer, programmable reset circuit, and enable input. It operates from 5.6 V to 31 V DC supply, delivers ±2% output voltage tolerance, maintains regulation under 40 V transients, and features 500 mV max dropout at 400 mA. It is designed for microprocessor power supply in engine control units (ECUs) and body control modules (BCMs).

For engineers reviewing the EV-AUTO-LDOS datasheet, EV-AUTO-LDOS pinout, EV-AUTO-LDOS application, or EV-AUTO-LDOS equivalent, key selection criteria include its wide input range (5.6–31 V), ultra-low quiescent current (3 µA disabled), thermal shutdown (150 °C trip), externally programmable reset delay (via capacitor on Vcr), and watchdog timeout (via capacitor on Vcw) - all critical for functional safety-compliant automotive subsystems.

Technical Context

The L4995 family uses a p-channel MOSFET pass element enabling low dropout operation independent of input transients up to 40 V. Regulation relies on a pre-trimmed reference voltage, achieving ±2% output accuracy across -40 °C to +150 °C junction temperature.

It integrates three supervisory functions: a reset circuit sensing output voltage down to 1 V with programmable delay (Vcr), a watchdog timer triggered by input frequency at Wi (L4995 variant only), and an active-high enable input (En) that controls regulator, reset, and watchdog activation simultaneously.

Key Specifications

Pinout & Package

EV-AUTO-LDOS is available in PowerSSO-12 and PowerSSO-24 thermally enhanced exposed-pad packages. Both variants feature multiple GND pins and substrate tab connections for optimal thermal dissipation in high-ambient automotive environments.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV73350PDBVR and TPS7B8150QDDARQ1, EV-AUTO-LDOS uniquely combines 500 mA capability, AEC-Q100 Grade 0 rating, and dual integrated watchdog + programmable reset - making it the only single-package solution for ASIL-B power supervision in high-temperature ECU designs.

Availability

EV-AUTO-LDOS is available at Aetrix Electronics and suitable for engine control units (ECUs), body control modules (BCMs), and advanced driver assistance system (ADAS) camera ECUs requiring stable component supply with automotive-grade reliability and long-term lifecycle support.

Supply support for EV-AUTO-LDOS 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

STMicroelectronics is a global semiconductor leader specializing in automotive, industrial, and power management solutions, with over 40 years of automotive qualification expertise and ISO/TS 16949 certified manufacturing.

The L4995 series was developed specifically for automotive microprocessor power domains, integrating supervision functions to simplify functional safety architecture and reduce system-level component count in ASIL-B compliant ECUs.

FAQ

What is the maximum input voltage transient the EV-AUTO-LDOS can withstand?

EV-AUTO-LDOS survives 40 V DC transients indefinitely per absolute maximum ratings, and is designed to handle ISO 7637-2 Pulse 5a (load dump) events without external protection. Its internal p-channel MOSFET pass element and robust ESD structure (±2 kV HBM, 750 V CDM) ensure reliability during battery disconnection or alternator surge events in 12 V and 24 V vehicle architectures.

How does the programmable reset delay work, and what capacitor value achieves a 50 ms delay?

The reset delay is set by an external capacitor (C_tr) between Vcr pin and GND. With C_tr = 47 nF, the typical delay is 33 ms (range 12–73 ms). For ~50 ms, a 68 nF capacitor yields 45–95 ms per datasheet Figure 29 and Table 6 (Trd vs Ctr). The delay is generated by internal charge/discharge current (8–30 µA) across C_tr, providing predictable, temperature-stable timing without crystal or RC oscillator drift.

Can EV-AUTO-LDOS be used in a 24 V commercial vehicle application?

Yes - its 5.6 V to 31 V operating range and 40 V absolute maximum input fully cover 24 V nominal systems, including cranking dips (~18 V) and load dump surges (~40 V). The -40 °C to +150 °C junction temperature rating and PowerSSO-24 package's 38 °C/W thermal resistance ensure reliable operation in heavy-duty truck ECUs where ambient temperatures exceed 105 °C.

Is the watchdog function mandatory, or can it be disabled?

The watchdog is optional and fully disableable: leave Wi pin unconnected or tie it to a fixed logic level (e.g., VS or GND) to prevent triggering. When unused, Vcw pin should be left floating. The L4995A and L4995R variants omit Wi/Vcw entirely; EV-AUTO-LDOS corresponds to the full-featured L4995 variant, giving designers flexibility to implement or omit watchdog based on ASIL decomposition requirements.