STMicroelectronics L4993MDTR

Overview

L4993MDTR from STMicroelectronics is an AEC-Q100 qualified automotive 5 V low-dropout linear voltage regulator with integrated reset and watchdog functions, delivering up to 150 mA output current, 400 mV dropout at full load, ±2% output voltage tolerance, and operation across 5.6 V–31 V input range - used to power microcontroller core logic and peripheral rails in engine control units.

For engineers reviewing the L4993MDTR datasheet, L4993MDTR pinout, L4993MDTR application, or L4993MDTR equivalent, key selection considerations include its programmable reset delay (via external capacitor on Vcr), watchdog timer adjustability (Vcw), thermal shutdown at 150°C, wide junction temperature range (−40°C to +150°C), and SO-20 package with multiple ground pins for enhanced thermal dissipation.

Technical Context

The L4993MDTR integrates a p-channel MOSFET pass element enabling regulation down to 400 mV dropout at 150 mA while maintaining stable 5 V output despite input transients up to 40 V. Its internal pre-trimmed reference ensures ±2% output accuracy over temperature and load.

Reset functionality monitors output voltage down to 1 V threshold and triggers a programmable delay (65–150 ms with 1 nF) before asserting open-drain Res output; watchdog activation requires WEn high and responds to low-frequency Wi input with adjustable timeout (25–90 ms via 47 nF on Vcw).

Key Specifications

Pinout & Package

Package: SO-20 (16+2+2 lead count), thermally enhanced with four dedicated Gnd pins (pins 4, 7, 15, 16) connected to internal heat spreader for R_th-jamb = 51°C/W on 6 cm² PCB copper area.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar automotive LDO-with-supervisor applications.

Compared with NCP380LSN33T2G and TPS7B6750QDDARQ1, the L4993MDTR uniquely integrates reset delay programming, watchdog timeout adjustment, and automotive-grade thermal/ESD robustness in a single SO-20 package - reducing component count and simplifying functional safety compliance.

Availability

L4993MDTR is available at Aetrix Electronics and suitable for engine control units, body control modules, ADAS camera ECUs, and transmission control modules requiring stable component supply with automotive qualification and long-term lifecycle support.

Supply support for L4993MDTR 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, designing and manufacturing automotive, industrial, and power management ICs with focus on reliability and functional safety.

The L4993MDTR belongs to ST's automotive voltage regulator product line, engineered specifically for microprocessor power supply in harsh environments where transient resilience, integrated supervision, and AEC-Q100 compliance are mandatory.

FAQ

What is the minimum input voltage required for regulation at full 150 mA load?

The L4993MDTR maintains 5 V regulation down to 5.4 V input at 150 mA due to its 400 mV dropout specification. Below this, output voltage drops linearly with input; the device remains functional but unregulated. Input must stay within 5.6 V–31 V operating range per datasheet Section 2.3.

Can the reset output (Res) drive a microcontroller's external reset pin directly?

Yes - Res is an open-drain output with internal 12–50 kΩ pull-up to Vos, capable of sinking ≥1 mA at 0.4 V. It can directly assert standard CMOS or Schmitt-trigger reset inputs; no external pull-up is needed unless interfacing with non-5 V logic families requiring different voltage levels.

How does the watchdog timer respond if the Wi input stops toggling?

When Wi frequency falls below the threshold (defined by Vwlth/Vwhth comparators), the watchdog asserts Res low after one full timeout period (e.g., 50 ms with 47 nF). The timeout is retriggered on each valid edge; cessation halts retriggering and causes reset after Twop expires.

Is the SO-20 package footprint compatible with standard SOIC-20 land patterns?

Yes - the L4993MDTR uses standard SO-20 (16+2+2) mechanical dimensions per Table 12 and Figure 37 in DS5285 Rev 10, matching JEDEC MS-013AC. Pin 1 is marked by notch; thermal pad is not present - all 20 leads are gull-wing surface-mount with 1.27 mm pitch.