STMicroelectronics L4938ND013TR

Overview

L4938ND013TR from STMicroelectronics is a dual low-dropout voltage regulator IC designed for automotive microcomputer power supply systems. It delivers a precision 5V ±2% standby output (VO1, 50mA) and a tracked/adjustable main output (VO2, up to 500mA), with integrated power-on reset, undervoltage warning, enable control, and thermal/short-circuit protection. It operates from 6–25V input, supports transient supply up to 40V, and achieves dropout as low as 0.2V (VO1) and 0.3V (VO2).

For engineers reviewing the L4938ND013TR datasheet, L4938ND013TR pinout, L4938ND013TR application, or L4938ND013TR equivalent, key selection criteria include dual-output tracking accuracy, sub-250µA quiescent current in standby mode, programmable VO2 (5–20V), EN-controlled disable, and automotive-grade transient tolerance (40V).

Technical Context

The L4938ND013TR integrates two independent LDO regulators: VO1 uses an isolated-collector vertical PNP for ultra-low dropout (≤0.4V at 50mA) and operation down to 2V input; VO2 employs the same topology but rated for 500mA, with tracking enabled when ADJ is tied to VO2 or adjustable via external resistor divider (VO2 = VO1 × (1 + R1/R2)).

Its auxiliary circuits include a voltage-sense comparator (1.23V reference, SI/SO pins) for early undervoltage warning, a power-on reset generator with externally timed delay (CT pin), and logic-level enable (VENH ≥ 2.4V) that disables VO2 while maintaining VO1 active - enabling true low-power standby states in ECU designs.

Key Specifications

Pinout & Package

Package: SO-20 (12+4+4 pin configuration, surface-mount, RoHS-compliant). Pin count and layout conform to JEDEC MO-166 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV70733PDRVR and TPS7B8750QKVURQ1, the L4938ND013TR uniquely integrates dual LDOs with tracking, programmability, reset, and sense in one SO-20 package - reducing bill-of-materials, PCB area, and validation effort for automotive ECUs requiring two tightly coupled supply rails.

Availability

L4938ND013TR is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS camera ECUs requiring stable component supply, automotive-grade transient resilience, and dual-rail power sequencing.

Supply support for L4938ND013TR 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 headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with broad manufacturing and quality certifications.

The L4938 series belongs to ST's automotive power management portfolio, engineered specifically for microcontroller-based vehicle systems requiring dual regulated supplies, functional safety awareness, and robustness against harsh electrical environments.

FAQ

What is the maximum allowable input voltage for continuous operation?

The L4938ND013TR supports continuous DC supply voltage up to 25 V (VS ≤ 25 V) across its operating temperature range (–40°C to +125°C). Transient input voltages up to 40 V are permitted for durations less than 1 second, complying with ISO 7637-2 Pulse 5a load-dump specifications commonly encountered in automotive 12 V systems.

How is the VO2 output voltage programmed using the ADJ pin?

VO2 is programmed by connecting an external resistor divider (R1, R2) between VO2, ADJ, and GND. The output follows VO2 = VO1 × (1 + R1/R2), where VO1 is the fixed 5 V standby rail. For example, R1 = 7.1 kΩ and R2 = 5.1 kΩ yields VO2 ≈ 12 V. When ADJ is directly tied to VO2, VO2 tracks VO1 at 5 V.

Does the L4938ND013TR provide reverse-battery protection?

No, the L4938ND013TR does not integrate reverse-battery protection. Its absolute maximum rating for VS is –0.3 V, meaning it will be damaged if subjected to reverse polarity. External protection - such as a series Schottky diode or MOSFET-based ideal diode circuit - must be implemented upstream of VS1/VS2 pins in battery-connected applications.

Can the RES and SO outputs drive standard logic inputs directly?

Yes - both RES and SO are open-drain outputs rated for 5 mA sink current and 20 V maximum output voltage. They can directly interface with CMOS or TTL logic inputs (e.g., MCU reset or interrupt pins) when pulled up to VO1 (5 V) or another compatible rail using a 10 kΩ resistor, as confirmed in the Electrical Characteristics table (VRL ≤ 0.4 V at 10 kΩ load).